diff --git a/doc/CMakeLists.txt b/doc/CMakeLists.txt
--- a/doc/CMakeLists.txt
+++ b/doc/CMakeLists.txt
@@ -13,6 +13,7 @@
     ADD_CUSTOM_TARGET(html
       COMMAND rm -rf gen-images
       COMMAND mkdir gen-images
+      COMMAND ${GHOSTSCRIPT_EXECUTABLE} -dNOPAUSE -dBATCH -q -dEPSCrop -dTextAlphaBits=4 -dGraphicsAlphaBits=4 -sDEVICE=pngalpha -r18 -sOutputFile=gen-images/grid_graph.png ${CMAKE_CURRENT_SOURCE_DIR}/images/grid_graph.eps
       COMMAND ${GHOSTSCRIPT_EXECUTABLE} -dNOPAUSE -dBATCH -q -dEPSCrop -dTextAlphaBits=4 -dGraphicsAlphaBits=4 -sDEVICE=pngalpha -r18 -sOutputFile=gen-images/nodeshape_0.png ${CMAKE_CURRENT_SOURCE_DIR}/images/nodeshape_0.eps
       COMMAND ${GHOSTSCRIPT_EXECUTABLE} -dNOPAUSE -dBATCH -q -dEPSCrop -dTextAlphaBits=4 -dGraphicsAlphaBits=4 -sDEVICE=pngalpha -r18 -sOutputFile=gen-images/nodeshape_1.png ${CMAKE_CURRENT_SOURCE_DIR}/images/nodeshape_1.eps
       COMMAND ${GHOSTSCRIPT_EXECUTABLE} -dNOPAUSE -dBATCH -q -dEPSCrop -dTextAlphaBits=4 -dGraphicsAlphaBits=4 -sDEVICE=pngalpha -r18 -sOutputFile=gen-images/nodeshape_2.png ${CMAKE_CURRENT_SOURCE_DIR}/images/nodeshape_2.eps
diff --git a/doc/Makefile.am b/doc/Makefile.am
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -14,6 +14,7 @@
 	doc/CMakeLists.txt
 
 DOC_EPS_IMAGES18 = \
+	grid_graph.eps \
 	nodeshape_0.eps \
 	nodeshape_1.eps \
 	nodeshape_2.eps \
diff --git a/doc/images/grid_graph.eps b/doc/images/grid_graph.eps
new file mode 100644
--- /dev/null
+++ b/doc/images/grid_graph.eps
@@ -0,0 +1,286 @@
+%!PS-Adobe-2.0 EPSF-2.0
+%%Title: Grid undirected graph
+%%Copyright: (C) 2006 LEMON Project
+%%Creator: LEMON, graphToEps()
+%%CreationDate: Fri Sep 29 11:55:56 2006
+%%BoundingBox: 0 0 985 1144
+%%EndComments
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+      2 index 1 index sub 2 index 2 index add lineto
+      2 index 1 index sub 2 index 2 index sub lineto
+      2 index 1 index add 2 index 2 index sub lineto
+      closepath pop pop pop} bind def
+/di { newpath 2 index 1 index add 2 index moveto
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+      2 index 1 index sub 2 index             lineto
+      2 index             2 index 2 index sub lineto
+      closepath pop pop pop} bind def
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diff --git a/lemon/Makefile.am b/lemon/Makefile.am
--- a/lemon/Makefile.am
+++ b/lemon/Makefile.am
@@ -29,6 +29,7 @@
         lemon/dim2.h \
 	lemon/error.h \
         lemon/graph_to_eps.h \
+        lemon/grid_graph.h \
 	lemon/kruskal.h \
 	lemon/lgf_reader.h \
 	lemon/lgf_writer.h \
diff --git a/lemon/grid_graph.h b/lemon/grid_graph.h
new file mode 100644
--- /dev/null
+++ b/lemon/grid_graph.h
@@ -0,0 +1,703 @@
+/* -*- mode: C++; indent-tabs-mode: nil; -*-
+ *
+ * This file is a part of LEMON, a generic C++ optimization library.
+ *
+ * Copyright (C) 2003-2008
+ * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
+ * (Egervary Research Group on Combinatorial Optimization, EGRES).
+ *
+ * Permission to use, modify and distribute this software is granted
+ * provided that this copyright notice appears in all copies. For
+ * precise terms see the accompanying LICENSE file.
+ *
+ * This software is provided "AS IS" with no warranty of any kind,
+ * express or implied, and with no claim as to its suitability for any
+ * purpose.
+ *
+ */
+
+#ifndef GRID_GRAPH_H
+#define GRID_GRAPH_H
+
+#include <lemon/core.h>
+#include <lemon/bits/graph_extender.h>
+#include <lemon/dim2.h>
+#include <lemon/assert.h>
+
+///\ingroup graphs
+///\file
+///\brief GridGraph class.
+
+namespace lemon {
+
+  class GridGraphBase {
+
+  public:
+
+    typedef GridGraphBase Graph;
+
+    class Node;
+    class Edge;
+    class Arc;
+
+  public:
+
+    GridGraphBase() {}
+
+  protected:
+
+    void construct(int width, int height) {
+       _width = width; _height = height;
+      _node_num = width * height;
+      _edge_num = 2 * _node_num - width - height;
+      _edge_limit = _node_num - _width;
+    }
+
+  public:
+
+    Node operator()(int i, int j) const {
+      LEMON_DEBUG(0 <= i && i < _width &&
+                  0 <= j  && j < _height, "Index out of range");
+      return Node(i + j * _width);
+    }
+
+    int col(Node n) const {
+      return n._id % _width;
+    }
+
+    int row(Node n) const {
+      return n._id / _width;
+    }
+
+    dim2::Point<int> pos(Node n) const {
+      return dim2::Point<int>(col(n), row(n));
+    }
+
+    int width() const {
+      return _width;
+    }
+
+    int height() const {
+      return _height;
+    }
+
+    typedef True NodeNumTag;
+    typedef True ArcNumTag;
+
+    int nodeNum() const { return _node_num; }
+    int edgeNum() const { return _edge_num; }
+    int arcNum() const { return 2 * _edge_num; }
+
+    Node u(Edge edge) const {
+      if (edge._id < _edge_limit) {
+        return edge._id;
+      } else {
+        return (edge._id - _edge_limit) % (_width - 1) +
+          (edge._id - _edge_limit) / (_width - 1) * _width;
+      }
+    }
+
+    Node v(Edge edge) const {
+      if (edge._id < _edge_limit) {
+        return edge._id + _width;
+      } else {
+        return (edge._id - _edge_limit) % (_width - 1) +
+          (edge._id - _edge_limit) / (_width - 1) * _width + 1;
+      }
+    }
+
+    Node source(Arc arc) const {
+      return (arc._id & 1) == 1 ? u(arc) : v(arc);
+    }
+
+    Node target(Arc arc) const {
+      return (arc._id & 1) == 1 ? v(arc) : u(arc);
+    }
+
+    static int id(Node node) { return node._id; }
+    static int id(Edge edge) { return edge._id; }
+    static int id(Arc arc) { return arc._id; }
+
+    int maxNodeId() const { return _node_num - 1; }
+    int maxEdgeId() const { return _edge_num - 1; }
+    int maxArcId() const { return 2 * _edge_num - 1; }
+
+    static Node nodeFromId(int id) { return Node(id);}
+    static Edge edgeFromId(int id) { return Edge(id);}
+    static Arc arcFromId(int id) { return Arc(id);}
+
+    typedef True FindEdgeTag;
+
+    Edge findEdge(Node u, Node v, Edge prev = INVALID) const {
+      if (prev != INVALID) return INVALID;
+      if (v._id > u._id) {
+        if (v._id - u._id == _width)
+          return Edge(u._id);
+        if (v._id - u._id == 1 && u._id % _width < _width - 1) {
+          return Edge(u._id / _width * (_width - 1) +
+                      u._id % _width + _edge_limit);
+        }
+      } else {
+        if (u._id - v._id == _width)
+          return Edge(v._id);
+        if (u._id - v._id == 1 && v._id % _width < _width - 1) {
+          return Edge(v._id / _width * (_width - 1) +
+                      v._id % _width + _edge_limit);
+        }
+      }
+      return INVALID;
+    }
+
+    Arc findArc(Node u, Node v, Arc prev = INVALID) const {
+      if (prev != INVALID) return INVALID;
+      if (v._id > u._id) {
+        if (v._id - u._id == _width)
+          return Arc((u._id << 1) | 1);
+        if (v._id - u._id == 1 && u._id % _width < _width - 1) {
+          return Arc(((u._id / _width * (_width - 1) +
+                       u._id % _width + _edge_limit) << 1) | 1);
+        }
+      } else {
+        if (u._id - v._id == _width)
+          return Arc(v._id << 1);
+        if (u._id - v._id == 1 && v._id % _width < _width - 1) {
+          return Arc((v._id / _width * (_width - 1) +
+                       v._id % _width + _edge_limit) << 1);
+        }
+      }
+      return INVALID;
+    }
+
+    class Node {
+      friend class GridGraphBase;
+
+    protected:
+      int _id;
+      Node(int id) : _id(id) {}
+    public:
+      Node() {}
+      Node (Invalid) : _id(-1) {}
+      bool operator==(const Node node) const {return _id == node._id;}
+      bool operator!=(const Node node) const {return _id != node._id;}
+      bool operator<(const Node node) const {return _id < node._id;}
+    };
+
+    class Edge {
+      friend class GridGraphBase;
+      friend class Arc;
+
+    protected:
+      int _id;
+
+      Edge(int id) : _id(id) {}
+
+    public:
+      Edge() {}
+      Edge (Invalid) : _id(-1) {}
+      bool operator==(const Edge edge) const {return _id == edge._id;}
+      bool operator!=(const Edge edge) const {return _id != edge._id;}
+      bool operator<(const Edge edge) const {return _id < edge._id;}
+    };
+
+    class Arc {
+      friend class GridGraphBase;
+
+    protected:
+      int _id;
+
+      Arc(int id) : _id(id) {}
+
+    public:
+      Arc() {}
+      Arc (Invalid) : _id(-1) {}
+      operator Edge() const { return _id != -1 ? Edge(_id >> 1) : INVALID; }
+      bool operator==(const Arc arc) const {return _id == arc._id;}
+      bool operator!=(const Arc arc) const {return _id != arc._id;}
+      bool operator<(const Arc arc) const {return _id < arc._id;}
+    };
+
+    static bool direction(Arc arc) {
+      return (arc._id & 1) == 1;
+    }
+
+    static Arc direct(Edge edge, bool dir) {
+      return Arc((edge._id << 1) | (dir ? 1 : 0));
+    }
+
+    void first(Node& node) const {
+      node._id = _node_num - 1;
+    }
+
+    static void next(Node& node) {
+      --node._id;
+    }
+
+    void first(Edge& edge) const {
+      edge._id = _edge_num - 1;
+    }
+
+    static void next(Edge& edge) {
+      --edge._id;
+    }
+
+    void first(Arc& arc) const {
+      arc._id = 2 * _edge_num - 1;
+    }
+
+    static void next(Arc& arc) {
+      --arc._id;
+    }
+
+    void firstOut(Arc& arc, const Node& node) const {
+      if (node._id % _width < _width - 1) {
+        arc._id = (_edge_limit + node._id % _width +
+                   (node._id / _width) * (_width - 1)) << 1 | 1;
+        return;
+      }
+      if (node._id < _node_num - _width) {
+        arc._id = node._id << 1 | 1;
+        return;
+      }
+      if (node._id % _width > 0) {
+        arc._id = (_edge_limit + node._id % _width +
+                   (node._id / _width) * (_width - 1) - 1) << 1;
+        return;
+      }
+      if (node._id >= _width) {
+        arc._id = (node._id - _width) << 1;
+        return;
+      }
+      arc._id = -1;
+    }
+
+    void nextOut(Arc& arc) const {
+      int nid = arc._id >> 1;
+      if ((arc._id & 1) == 1) {
+        if (nid >= _edge_limit) {
+          nid = (nid - _edge_limit) % (_width - 1) +
+            (nid - _edge_limit) / (_width - 1) * _width;
+          if (nid < _node_num - _width) {
+            arc._id = nid << 1 | 1;
+            return;
+          }
+        }
+        if (nid % _width > 0) {
+          arc._id = (_edge_limit + nid % _width +
+                     (nid / _width) * (_width - 1) - 1) << 1;
+          return;
+        }
+        if (nid >= _width) {
+          arc._id = (nid - _width) << 1;
+          return;
+        }
+      } else {
+        if (nid >= _edge_limit) {
+          nid = (nid - _edge_limit) % (_width - 1) +
+            (nid - _edge_limit) / (_width - 1) * _width + 1;
+          if (nid >= _width) {
+            arc._id = (nid - _width) << 1;
+            return;
+          }
+        }
+      }
+      arc._id = -1;
+    }
+
+    void firstIn(Arc& arc, const Node& node) const {
+      if (node._id % _width < _width - 1) {
+        arc._id = (_edge_limit + node._id % _width +
+                   (node._id / _width) * (_width - 1)) << 1;
+        return;
+      }
+      if (node._id < _node_num - _width) {
+        arc._id = node._id << 1;
+        return;
+      }
+      if (node._id % _width > 0) {
+        arc._id = (_edge_limit + node._id % _width +
+                   (node._id / _width) * (_width - 1) - 1) << 1 | 1;
+        return;
+      }
+      if (node._id >= _width) {
+        arc._id = (node._id - _width) << 1 | 1;
+        return;
+      }
+      arc._id = -1;
+    }
+
+    void nextIn(Arc& arc) const {
+      int nid = arc._id >> 1;
+      if ((arc._id & 1) == 0) {
+        if (nid >= _edge_limit) {
+          nid = (nid - _edge_limit) % (_width - 1) +
+            (nid - _edge_limit) / (_width - 1) * _width;
+          if (nid < _node_num - _width) {
+            arc._id = nid << 1;
+            return;
+          }
+        }
+        if (nid % _width > 0) {
+          arc._id = (_edge_limit + nid % _width +
+                     (nid / _width) * (_width - 1) - 1) << 1 | 1;
+          return;
+        }
+        if (nid >= _width) {
+          arc._id = (nid - _width) << 1 | 1;
+          return;
+        }
+      } else {
+        if (nid >= _edge_limit) {
+          nid = (nid - _edge_limit) % (_width - 1) +
+            (nid - _edge_limit) / (_width - 1) * _width + 1;
+          if (nid >= _width) {
+            arc._id = (nid - _width) << 1 | 1;
+            return;
+          }
+        }
+      }
+      arc._id = -1;
+    }
+
+    void firstInc(Edge& edge, bool& dir, const Node& node) const {
+      if (node._id % _width < _width - 1) {
+        edge._id = _edge_limit + node._id % _width +
+          (node._id / _width) * (_width - 1);
+        dir = true;
+        return;
+      }
+      if (node._id < _node_num - _width) {
+        edge._id = node._id;
+        dir = true;
+        return;
+      }
+      if (node._id % _width > 0) {
+        edge._id = _edge_limit + node._id % _width +
+          (node._id / _width) * (_width - 1) - 1;
+        dir = false;
+        return;
+      }
+      if (node._id >= _width) {
+        edge._id = node._id - _width;
+        dir = false;
+        return;
+      }
+      edge._id = -1;
+      dir = true;
+    }
+
+    void nextInc(Edge& edge, bool& dir) const {
+      int nid = edge._id;
+      if (dir) {
+        if (nid >= _edge_limit) {
+          nid = (nid - _edge_limit) % (_width - 1) +
+            (nid - _edge_limit) / (_width - 1) * _width;
+          if (nid < _node_num - _width) {
+            edge._id = nid;
+            return;
+          }
+        }
+        if (nid % _width > 0) {
+          edge._id = _edge_limit + nid % _width +
+            (nid / _width) * (_width - 1) - 1;
+          dir = false;
+          return;
+        }
+        if (nid >= _width) {
+          edge._id = nid - _width;
+          dir = false;
+          return;
+        }
+      } else {
+        if (nid >= _edge_limit) {
+          nid = (nid - _edge_limit) % (_width - 1) +
+            (nid - _edge_limit) / (_width - 1) * _width + 1;
+          if (nid >= _width) {
+            edge._id = nid - _width;
+            return;
+          }
+        }
+      }
+      edge._id = -1;
+      dir = true;
+    }
+
+    Arc right(Node n) const {
+      if (n._id % _width < _width - 1) {
+        return Arc(((_edge_limit + n._id % _width +
+                    (n._id / _width) * (_width - 1)) << 1) | 1);
+      } else {
+        return INVALID;
+      }
+    }
+
+    Arc left(Node n) const {
+      if (n._id % _width > 0) {
+        return Arc((_edge_limit + n._id % _width +
+                     (n._id / _width) * (_width - 1) - 1) << 1);
+      } else {
+        return INVALID;
+      }
+    }
+
+    Arc up(Node n) const {
+      if (n._id < _edge_limit) {
+        return Arc((n._id << 1) | 1);
+      } else {
+        return INVALID;
+      }
+    }
+
+    Arc down(Node n) const {
+      if (n._id >= _width) {
+        return Arc((n._id - _width) << 1);
+      } else {
+        return INVALID;
+      }
+    }
+
+  private:
+    int _width, _height;
+    int _node_num, _edge_num;
+    int _edge_limit;
+  };
+
+
+  typedef GraphExtender<GridGraphBase> ExtendedGridGraphBase;
+
+  /// \ingroup graphs
+  ///
+  /// \brief Grid graph class
+  ///
+  /// This class implements a special graph type. The nodes of the
+  /// graph can be indexed by two integer \c (i,j) value where \c i is
+  /// in the \c [0..width()-1] range and j is in the \c
+  /// [0..height()-1] range.  Two nodes are connected in the graph if
+  /// the indexes differ exactly on one position and exactly one is
+  /// the difference. The nodes of the graph can be indexed by position
+  /// with the \c operator()() function. The positions of the nodes can be
+  /// get with \c pos(), \c col() and \c row() members. The outgoing
+  /// arcs can be retrieved with the \c right(), \c up(), \c left()
+  /// and \c down() functions, where the bottom-left corner is the
+  /// origin.
+  ///
+  /// \image html grid_graph.png
+  /// \image latex grid_graph.eps "Grid graph" row_num=\textrow_num
+  ///
+  /// A short example about the basic usage:
+  ///\code
+  /// GridGraph graph(rows, cols);
+  /// GridGraph::NodeMap<int> val(graph);
+  /// for (int i = 0; i < graph.width(); ++i) {
+  ///   for (int j = 0; j < graph.height(); ++j) {
+  ///     val[graph(i, j)] = i + j;
+  ///   }
+  /// }
+  ///\endcode
+  ///
+  /// This graph type is fully conform to the \ref concepts::Graph
+  /// "Graph" concept, and it also has an important extra feature
+  /// that its maps are real \ref concepts::ReferenceMap
+  /// "reference map"s.
+  class GridGraph : public ExtendedGridGraphBase {
+  public:
+
+    typedef ExtendedGridGraphBase Parent;
+
+    /// \brief Map to get the indices of the nodes as dim2::Point<int>.
+    ///
+    /// Map to get the indices of the nodes as dim2::Point<int>.
+    class IndexMap {
+    public:
+      /// \brief The key type of the map
+      typedef GridGraph::Node Key;
+      /// \brief The value type of the map
+      typedef dim2::Point<int> Value;
+
+      /// \brief Constructor
+      ///
+      /// Constructor
+      IndexMap(const GridGraph& graph) : _graph(graph) {}
+
+      /// \brief The subscript operator
+      ///
+      /// The subscript operator.
+      Value operator[](Key key) const {
+        return _graph.pos(key);
+      }
+
+    private:
+      const GridGraph& _graph;
+    };
+
+    /// \brief Map to get the column of the nodes.
+    ///
+    /// Map to get the column of the nodes.
+    class ColMap {
+    public:
+      /// \brief The key type of the map
+      typedef GridGraph::Node Key;
+      /// \brief The value type of the map
+      typedef int Value;
+
+      /// \brief Constructor
+      ///
+      /// Constructor
+      ColMap(const GridGraph& graph) : _graph(graph) {}
+
+      /// \brief The subscript operator
+      ///
+      /// The subscript operator.
+      Value operator[](Key key) const {
+        return _graph.col(key);
+      }
+
+    private:
+      const GridGraph& _graph;
+    };
+
+    /// \brief Map to get the row of the nodes.
+    ///
+    /// Map to get the row of the nodes.
+    class RowMap {
+    public:
+      /// \brief The key type of the map
+      typedef GridGraph::Node Key;
+      /// \brief The value type of the map
+      typedef int Value;
+
+      /// \brief Constructor
+      ///
+      /// Constructor
+      RowMap(const GridGraph& graph) : _graph(graph) {}
+
+      /// \brief The subscript operator
+      ///
+      /// The subscript operator.
+      Value operator[](Key key) const {
+        return _graph.row(key);
+      }
+
+    private:
+      const GridGraph& _graph;
+    };
+
+    /// \brief Constructor
+    ///
+    /// Construct a grid graph with given size.
+    GridGraph(int width, int height) { construct(width, height); }
+
+    /// \brief Resize the graph
+    ///
+    /// Resize the graph. The function will fully destroy and rebuild
+    /// the graph.  This cause that the maps of the graph will
+    /// reallocated automatically and the previous values will be
+    /// lost.
+    void resize(int width, int height) {
+      Parent::notifier(Arc()).clear();
+      Parent::notifier(Edge()).clear();
+      Parent::notifier(Node()).clear();
+      construct(width, height);
+      Parent::notifier(Node()).build();
+      Parent::notifier(Edge()).build();
+      Parent::notifier(Arc()).build();
+    }
+
+    /// \brief The node on the given position.
+    ///
+    /// Gives back the node on the given position.
+    Node operator()(int i, int j) const {
+      return Parent::operator()(i, j);
+    }
+
+    /// \brief Gives back the column index of the node.
+    ///
+    /// Gives back the column index of the node.
+    int col(Node n) const {
+      return Parent::col(n);
+    }
+
+    /// \brief Gives back the row index of the node.
+    ///
+    /// Gives back the row index of the node.
+    int row(Node n) const {
+      return Parent::row(n);
+    }
+
+    /// \brief Gives back the position of the node.
+    ///
+    /// Gives back the position of the node, ie. the <tt>(col,row)</tt> pair.
+    dim2::Point<int> pos(Node n) const {
+      return Parent::pos(n);
+    }
+
+    /// \brief Gives back the number of the columns.
+    ///
+    /// Gives back the number of the columns.
+    int width() const {
+      return Parent::width();
+    }
+
+    /// \brief Gives back the number of the rows.
+    ///
+    /// Gives back the number of the rows.
+    int height() const {
+      return Parent::height();
+    }
+
+    /// \brief Gives back the arc goes right from the node.
+    ///
+    /// Gives back the arc goes right from the node. If there is not
+    /// outgoing arc then it gives back INVALID.
+    Arc right(Node n) const {
+      return Parent::right(n);
+    }
+
+    /// \brief Gives back the arc goes left from the node.
+    ///
+    /// Gives back the arc goes left from the node. If there is not
+    /// outgoing arc then it gives back INVALID.
+    Arc left(Node n) const {
+      return Parent::left(n);
+    }
+
+    /// \brief Gives back the arc goes up from the node.
+    ///
+    /// Gives back the arc goes up from the node. If there is not
+    /// outgoing arc then it gives back INVALID.
+    Arc up(Node n) const {
+      return Parent::up(n);
+    }
+
+    /// \brief Gives back the arc goes down from the node.
+    ///
+    /// Gives back the arc goes down from the node. If there is not
+    /// outgoing arc then it gives back INVALID.
+    Arc down(Node n) const {
+      return Parent::down(n);
+    }
+
+    /// \brief Index map of the grid graph
+    ///
+    /// Just returns an IndexMap for the grid graph.
+    IndexMap indexMap() const {
+      return IndexMap(*this);
+    }
+
+    /// \brief Row map of the grid graph
+    ///
+    /// Just returns a RowMap for the grid graph.
+    RowMap rowMap() const {
+      return RowMap(*this);
+    }
+
+    /// \brief Column map of the grid graph
+    ///
+    /// Just returns a ColMap for the grid graph.
+    ColMap colMap() const {
+      return ColMap(*this);
+    }
+
+  };
+
+}
+#endif
diff --git a/test/graph_test.cc b/test/graph_test.cc
--- a/test/graph_test.cc
+++ b/test/graph_test.cc
@@ -20,7 +20,7 @@
 #include <lemon/list_graph.h>
 #include <lemon/smart_graph.h>
 // #include <lemon/full_graph.h>
-// #include <lemon/grid_graph.h>
+#include <lemon/grid_graph.h>
 
 #include "test_tools.h"
 #include "graph_test.h"
@@ -128,10 +128,9 @@
 //    checkConcept<Graph, FullGraph>();
 //    checkGraphIterators<FullGraph>();
 //  }
-//  { // Checking GridGraph
-//    checkConcept<Graph, GridGraph>();
-//    checkGraphIterators<GridGraph>();
-//  }
+  { // Checking GridGraph
+    checkConcept<Graph, GridGraph>();
+  }
 }
 
 template <typename Graph>
@@ -188,49 +187,84 @@
   check(!g.valid(g.arcFromId(-1)), "Wrong validity check");
 }
 
-// void checkGridGraph(const GridGraph& g, int w, int h) {
-//   check(g.width() == w, "Wrong width");
-//   check(g.height() == h, "Wrong height");
+void checkGridGraph(int width, int height) {
+  typedef GridGraph Graph;
+  GRAPH_TYPEDEFS(Graph);
+  Graph G(width, height);
 
-//   for (int i = 0; i < w; ++i) {
-//     for (int j = 0; j < h; ++j) {
-//       check(g.col(g(i, j)) == i, "Wrong col");
-//       check(g.row(g(i, j)) == j, "Wrong row");
-//     }
-//   }
+  check(G.width() == width, "Wrong column number");
+  check(G.height() == height, "Wrong row number");
 
-//   for (int i = 0; i < w; ++i) {
-//     for (int j = 0; j < h - 1; ++j) {
-//       check(g.source(g.down(g(i, j))) == g(i, j), "Wrong down");
-//       check(g.target(g.down(g(i, j))) == g(i, j + 1), "Wrong down");
-//     }
-//     check(g.down(g(i, h - 1)) == INVALID, "Wrong down");
-//   }
+  for (int i = 0; i < width; ++i) {
+    for (int j = 0; j < height; ++j) {
+      check(G.col(G(i, j)) == i, "Wrong column");
+      check(G.row(G(i, j)) == j, "Wrong row");
+      check(G.pos(G(i, j)).x == i, "Wrong column");
+      check(G.pos(G(i, j)).y == j, "Wrong row");
+    }
+  }
 
-//   for (int i = 0; i < w; ++i) {
-//     for (int j = 1; j < h; ++j) {
-//       check(g.source(g.up(g(i, j))) == g(i, j), "Wrong up");
-//       check(g.target(g.up(g(i, j))) == g(i, j - 1), "Wrong up");
-//     }
-//     check(g.up(g(i, 0)) == INVALID, "Wrong up");
-//   }
+  for (int j = 0; j < height; ++j) {
+    for (int i = 0; i < width - 1; ++i) {
+      check(G.source(G.right(G(i, j))) == G(i, j), "Wrong right");
+      check(G.target(G.right(G(i, j))) == G(i + 1, j), "Wrong right");
+    }
+    check(G.right(G(width - 1, j)) == INVALID, "Wrong right");
+  }
 
-//   for (int j = 0; j < h; ++j) {
-//     for (int i = 0; i < w - 1; ++i) {
-//       check(g.source(g.right(g(i, j))) == g(i, j), "Wrong right");
-//       check(g.target(g.right(g(i, j))) == g(i + 1, j), "Wrong right");
-//     }
-//     check(g.right(g(w - 1, j)) == INVALID, "Wrong right");
-//   }
+  for (int j = 0; j < height; ++j) {
+    for (int i = 1; i < width; ++i) {
+      check(G.source(G.left(G(i, j))) == G(i, j), "Wrong left");
+      check(G.target(G.left(G(i, j))) == G(i - 1, j), "Wrong left");
+    }
+    check(G.left(G(0, j)) == INVALID, "Wrong left");
+  }
 
-//   for (int j = 0; j < h; ++j) {
-//     for (int i = 1; i < w; ++i) {
-//       check(g.source(g.left(g(i, j))) == g(i, j), "Wrong left");
-//       check(g.target(g.left(g(i, j))) == g(i - 1, j), "Wrong left");
-//     }
-//     check(g.left(g(0, j)) == INVALID, "Wrong left");
-//   }
-// }
+  for (int i = 0; i < width; ++i) {
+    for (int j = 0; j < height - 1; ++j) {
+      check(G.source(G.up(G(i, j))) == G(i, j), "Wrong up");
+      check(G.target(G.up(G(i, j))) == G(i, j + 1), "Wrong up");
+    }
+    check(G.up(G(i, height - 1)) == INVALID, "Wrong up");
+  }
+
+  for (int i = 0; i < width; ++i) {
+    for (int j = 1; j < height; ++j) {
+      check(G.source(G.down(G(i, j))) == G(i, j), "Wrong down");
+      check(G.target(G.down(G(i, j))) == G(i, j - 1), "Wrong down");
+    }
+    check(G.down(G(i, 0)) == INVALID, "Wrong down");
+  }
+
+  checkGraphNodeList(G, width * height);
+  checkGraphEdgeList(G, width * (height - 1) + (width - 1) * height);
+  checkGraphArcList(G, 2 * (width * (height - 1) + (width - 1) * height));
+
+  for (NodeIt n(G); n != INVALID; ++n) {
+    int nb = 4;
+    if (G.col(n) == 0) --nb;
+    if (G.col(n) == width - 1) --nb;
+    if (G.row(n) == 0) --nb;
+    if (G.row(n) == height - 1) --nb;
+
+    checkGraphOutArcList(G, n, nb);
+    checkGraphInArcList(G, n, nb);
+    checkGraphIncEdgeList(G, n, nb);
+  }
+
+  checkArcDirections(G);
+
+  checkGraphConArcList(G, 2 * (width * (height - 1) + (width - 1) * height));
+  checkGraphConEdgeList(G, width * (height - 1) + (width - 1) * height);
+
+  checkNodeIds(G);
+  checkArcIds(G);
+  checkEdgeIds(G);
+  checkGraphNodeMap(G);
+  checkGraphArcMap(G);
+  checkGraphEdgeMap(G);
+
+}
 
 void checkGraphs() {
   { // Checking ListGraph
@@ -246,12 +280,13 @@
 //     checkGraphNodeList(g, 5);
 //     checkGraphEdgeList(g, 10);
 //   }
-//   { // Checking GridGraph
-//     GridGraph g(5, 6);
-//     checkGraphNodeList(g, 30);
-//     checkGraphEdgeList(g, 49);
-//     checkGridGraph(g, 5, 6);
-//   }
+  { // Checking GridGraph
+    checkGridGraph(5, 8);
+    checkGridGraph(8, 5);
+    checkGridGraph(5, 5);
+    checkGridGraph(0, 0);
+    checkGridGraph(1, 1);
+  }
 }
 
 int main() {