diff --git a/src/main.rs b/src/main.rs
index 13a6d94..f31e381 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,3 +1,5 @@
+mod world;
+
 use noise::{Perlin, ScalePoint, Add, NoiseFn, Multiply, ScaleBias};
 use noise::utils::{NoiseMapBuilder, PlaneMapBuilder};
 use image::{RgbImage, Rgb};
@@ -72,31 +74,14 @@ fn main() {
 
     let mut img = RgbImage::new(map_size as u32, map_size as u32);
 
+    let mut world = world::World::new(map_size);
+
     for x in 0..map_size {
         for y in 0..map_size {
             let h = plane.get_value(x, y);
-            if h < -2000.0 {
-                // deep ocean
-                img.put_pixel(x as u32, y as u32, Rgb([20, 60, 255]));
-            } else if h < 0.0 {
-                // ocean
-                img.put_pixel(x as u32, y as u32, Rgb([20, 120, 255]));
-            } else if h < 10.0 {
-                // beach
-                img.put_pixel(x as u32, y as u32, Rgb([255, 255, 100]));
-            } else if h < 1000.0 {
-                // grass
-                img.put_pixel(x as u32, y as u32, Rgb([0, 204, 0]));
-            } else if h < 2000.0 {
-                // hills
-                img.put_pixel(x as u32, y as u32, Rgb([102, 153, 0]));
-            } else if h < 3500.0 {
-                // mountains
-                img.put_pixel(x as u32, y as u32, Rgb([153, 153, 102]));
-            } else {
-                // snow
-                img.put_pixel(x as u32, y as u32, Rgb([230, 230, 230]));
-            }
+            let t = world::Terrain::from_height(h);
+            world.map[x][y] = t;
+            img.put_pixel(x as u32, y as u32, Rgb(t.to_color()));
         }
     }
     img.save("world.png").unwrap();
diff --git a/src/world.rs b/src/world.rs
new file mode 100644
index 0000000..e1a5c85
--- /dev/null
+++ b/src/world.rs
@@ -0,0 +1,65 @@
+
+#[derive(Debug, Clone, Copy)]
+pub enum Terrain {
+    DeepOcean,
+    Ocean,
+    Beach,
+    Flats,
+    Hills,
+    Mountains,
+    HighMountains,
+}
+
+pub struct World {
+    pub map: Vec<Vec<Terrain>>,
+    pub size: usize,
+}
+
+impl World {
+    pub fn new(size: usize) -> World {
+        let mut map = Vec::new();
+        for _ in 0..size {
+            let mut row = Vec::new();
+            for _ in 0..size {
+                row.push(Terrain::DeepOcean);
+            }
+            map.push(row);
+        }
+        World {
+            map: map,
+            size: size,
+        }
+    }
+}
+
+impl Terrain {
+    pub fn from_height(height: f64) -> Terrain {
+        if height < -2000.0 {
+            Terrain::DeepOcean
+        } else if height < 0.0 {
+            Terrain::Ocean
+        } else if height < 50.0 {
+            Terrain::Beach
+        } else if height < 1000.0 {
+            Terrain::Flats
+        } else if height < 2000.0 {
+            Terrain::Hills
+        } else if height < 3500.0 {
+            Terrain::Mountains
+        } else {
+            Terrain::HighMountains
+        }
+    }
+
+    pub fn to_color(self) -> [u8; 3] {
+        match self {
+            Terrain::DeepOcean => [20, 60, 255],
+            Terrain::Ocean => [20, 120, 255],
+            Terrain::Beach => [255, 255, 100],
+            Terrain::Flats => [0, 204, 0],
+            Terrain::Hills => [102, 153, 0],
+            Terrain::Mountains => [153, 153, 102],
+            Terrain::HighMountains => [230, 230, 230],
+        }
+    }
+}