diff --git a/src/colony.cpp b/src/colony.cpp
new file mode 100644
index 0000000..a8b2efd
--- /dev/null
+++ b/src/colony.cpp
@@ -0,0 +1,15 @@
+#include "colony.hpp"
+#include "ant.hpp"
+
+Colony::Colony(double x, double y)
+  : x(x), y(y) {
+  appearance = sf::CircleShape(25);
+  appearance.setFillColor(sf::Color::Red);
+  appearance.setPosition(x - appearance.getRadius(), y - appearance.getRadius());
+}
+
+// TODO: don't use appearance for this, add radius field
+bool Colony::antIsHome(const Ant& ant) const {
+  return ant.x > x - appearance.getRadius() && ant.x < x + appearance.getRadius()
+    && ant.y > y - appearance.getRadius() && ant.y < y + appearance.getRadius();
+}
diff --git a/src/colony.hpp b/src/colony.hpp
new file mode 100644
index 0000000..032535f
--- /dev/null
+++ b/src/colony.hpp
@@ -0,0 +1,20 @@
+#ifndef __COLONY_H_
+#define __COLONY_H_
+
+#include <SFML/Graphics.hpp>
+
+class Ant; // Colony and Ant can't include eachother so forward-declare
+
+class Colony {
+  double x, y;
+
+public:
+  sf::CircleShape appearance;
+
+public:
+  Colony(double x, double y);
+
+  bool antIsHome(const Ant& ant) const;
+};
+
+#endif // __COLONY_H_