diff --git a/README.rst b/README.rst
index b8aeaf0..69d093a 100644
--- a/README.rst
+++ b/README.rst
@@ -55,6 +55,9 @@ drawplayers:
 draworigin:
     Draw origin indicator, `--draworigin`
 
+geometry:
+    Limit area to specific geometry, `--geometry -800:-800+1600+1600`
+
 Customization of colors.txt
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
diff --git a/TileGenerator.cpp b/TileGenerator.cpp
index 9feabd6..77f8681 100644
--- a/TileGenerator.cpp
+++ b/TileGenerator.cpp
@@ -97,7 +97,11 @@ TileGenerator::TileGenerator():
 	m_xMin(0),
 	m_xMax(0),
 	m_zMin(0),
-	m_zMax(0)
+	m_zMax(0),
+	m_geomX(-50),
+	m_geomY(-50),
+	m_geomX2(50),
+	m_geomY2(50)
 {
 	string colors_txt_data(reinterpret_cast<char *>(colors_txt), colors_txt_len);
 	istringstream colors_stream(colors_txt_data);
@@ -168,6 +172,38 @@ void TileGenerator::setDrawScale(bool drawScale)
 	}
 }
 
+void TileGenerator::setGeometry(int x, int y, int w, int h)
+{
+	if (x > 0) {
+		m_geomX = (x + 15) / 16;
+	}
+	else {
+		m_geomX = (x - 15) / 16;
+	}
+	if (y > 0) {
+		m_geomY = (y + 15) / 16;
+	}
+	else {
+		m_geomY = (y - 15) / 16;
+	}
+
+	int x2 = x + w;
+	int y2 = y + h;
+
+	if (x2 > 0) {
+		m_geomX2 = (x2 + 15) / 16;
+	}
+	else {
+		m_geomX2 = (x2 - 15) / 16;
+	}
+	if (y2 > 0) {
+		m_geomY2 = (y2 + 15) / 16;
+	}
+	else {
+		m_geomY2 = (y2 - 15) / 16;
+	}
+}
+
 void TileGenerator::parseColorsFile(const std::string &fileName)
 {
 	ifstream in;
@@ -248,6 +284,9 @@ void TileGenerator::loadBlocks()
 			if(result == SQLITE_ROW) {
 				sqlite3_int64 blocknum = sqlite3_column_int64(statement, 0);
 				BlockPos pos = decodeBlockPos(blocknum);
+				if (pos.x < m_geomX || pos.x >= m_geomX2 || pos.z < m_geomY || pos.z >= m_geomY2) {
+					continue;
+				}
 				if (pos.x < m_xMin) {
 					m_xMin = pos.x;
 				}
diff --git a/TileGenerator.h b/TileGenerator.h
index acd9dbb..a877eea 100644
--- a/TileGenerator.h
+++ b/TileGenerator.h
@@ -84,6 +84,7 @@ public:
 	void setDrawOrigin(bool drawOrigin);
 	void setDrawPlayers(bool drawPlayers);
 	void setDrawScale(bool drawScale);
+	void setGeometry(int x, int y, int w, int h);
 	void parseColorsFile(const std::string &fileName);
 	void generate(const std::string &input, const std::string &output);
 
@@ -123,6 +124,10 @@ private:
 	int m_xMax;
 	int m_zMin;
 	int m_zMax;
+	int m_geomX;
+	int m_geomY;
+	int m_geomX2;
+	int m_geomY2;
 	int m_mapWidth;
 	int m_mapHeight;
 	std::list<std::pair<int, int> > m_positions;
diff --git a/mapper.cpp b/mapper.cpp
index 70482ed..99b3b99 100644
--- a/mapper.cpp
+++ b/mapper.cpp
@@ -12,6 +12,7 @@
 #include <iostream>
 #include <map>
 #include <string>
+#include <sstream>
 #include "TileGenerator.h"
 
 using namespace std;
@@ -28,6 +29,7 @@ void usage()
   --drawscale\n\
   --drawplayers\n\
   --draworigin\n\
+  --geometry x:y+w+h\n\
 Color format: '#000000'\n";
 	std::cout << usage_text;
 }
@@ -46,6 +48,7 @@ int main(int argc, char *argv[])
 		{"draworigin", no_argument, 0, 'R'},
 		{"drawplayers", no_argument, 0, 'P'},
 		{"drawscale", no_argument, 0, 'S'},
+		{"geometry", required_argument, 0, 'g'},
 	};
 
 	string input;
@@ -96,6 +99,19 @@ int main(int argc, char *argv[])
 			case 'S':
 				generator.setDrawScale(true);
 				break;
+			case 'g': {
+					istringstream geometry;
+					geometry.str(optarg);
+					int x, y, w, h;
+					char c;
+					geometry >> x >> c >> y >> w >> h;
+					if (geometry.fail() || c != ':' || w < 1 || h < 1) {
+						usage();
+						exit(-1);
+					}
+					generator.setGeometry(x, y, w, h);
+				}
+				break;
 			default:
 				abort();
 		}