diff --git a/src/lib.rs b/src/lib.rs
index eddc1ab..7468e6a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -2,45 +2,39 @@ pub mod colour;
 pub mod palette;
 pub mod image;
 pub mod mocks;
+pub mod tile;
 
 use colour::Colour;
 use palette::Palette;
 use image::Image;
+use tile::Tile;
 
 #[derive(Debug, Eq, PartialEq)]
-struct Tile {
-    id: String, // base36 string
-    name: Option<String>,
-    wall: bool,
-    animation_frames: Vec<Image>,
-}
-
-#[derive(Debug, Eq, PartialEq)]
-struct Position {
+pub struct Position {
     x: u8,
     y: u8,
 }
 
 #[derive(Debug, Eq, PartialEq)]
-struct Instance {
+pub struct Instance {
     position: Position,
     id: String, // item / ending id
 }
 
 #[derive(Debug, Eq, PartialEq)]
-struct ExitInstance {
+pub struct ExitInstance {
     position: Position,
     exit: Exit,
 }
 
 #[derive(Debug, Eq, PartialEq)]
-struct Dialogue {
+pub struct Dialogue {
     id: String,
     contents: String,
 }
 
 #[derive(Debug, Eq, PartialEq)]
-struct Sprite {
+pub struct Sprite {
     id: String, // lowercase base36
     name: Option<String>,
     animation_frames: Vec<Image>,
@@ -58,7 +52,7 @@ pub struct Avatar {
 }
 
 #[derive(Debug, Eq, PartialEq)]
-struct Item {
+pub struct Item {
     id: String,
     animation_frames: Vec<Image>,
     name: Option<String>,
@@ -66,7 +60,7 @@ struct Item {
 }
 
 #[derive(Debug, Eq, PartialEq)]
-struct Exit {
+pub struct Exit {
     /// destination
     room: String,  /// id
     position: Position,
@@ -74,13 +68,13 @@ struct Exit {
 
 // same as a dialogue basically
 #[derive(Debug, Eq, PartialEq)]
-struct Ending {
+pub struct Ending {
     id: String,
     dialogue: String,
 }
 
 #[derive(Debug, Eq, PartialEq)]
-struct Room {
+pub struct Room {
     id: String,
     palette: String, // id
     name: Option<String>,
@@ -91,13 +85,13 @@ struct Room {
 }
 
 #[derive(Debug, Eq, PartialEq)]
-struct Variable {
+pub struct Variable {
     id: String,
     initial_value: String,
 }
 
 #[derive(Debug, PartialEq)]
-struct Game {
+pub struct Game {
     name: String,
     version: f64,
     room_format: u8,
@@ -373,88 +367,6 @@ impl AnimationFrames for Vec<Image> {
     }
 }
 
-impl From<String> for Tile {
-    fn from(string: String) -> Tile {
-        let mut lines: Vec<&str> = string.lines().collect();
-
-        let id = lines[0].replace("TIL ", "");
-
-        let last_line = lines.pop().unwrap();
-        let wall = match last_line == "WAL true" {
-            true => true,
-            false => {
-                lines.push(last_line);
-                false
-            }
-        };
-
-        let last_line = lines.pop().unwrap();
-        let name = match last_line.starts_with("NAME") {
-            true => Some(last_line.replace("NAME ", "").to_string()),
-            false => {
-                lines.push(last_line);
-                None
-            }
-        };
-
-        let animation_frames = lines[1..].join("");
-        let animation_frames: Vec<&str> = animation_frames.split("\n>\n").collect();
-        let animation_frames: Vec<Image> = animation_frames.iter().map(|&frame| {
-            Image::from(frame.to_string())
-        }).collect();
-
-        Tile { id, name, wall, animation_frames }
-    }
-}
-
-#[test]
-fn test_tile_from_string() {
-    let output = Tile::from(include_str!("../test/resources/tile").to_string());
-    
-    let expected = Tile {
-        id: "z".to_string(),
-        name: Some("concrete 1".to_string()),
-        wall: true,
-        animation_frames: vec![
-            Image {
-                pixels: vec![1; 64]
-            }
-        ],
-    };
-    
-    assert_eq!(output, expected);
-}
-
-impl ToString for Tile {
-    #[inline]
-    fn to_string(&self) -> String {
-        format!(
-            "TIL {}\n{}{}{}",
-            self.id,
-            self.animation_frames.to_string(),
-            if self.name.as_ref().is_some() { format!("\nNAME {}", self.name.as_ref().unwrap())} else {"".to_string() },
-            if self.wall {"\nWAL true"} else {""}
-        )
-    }
-}
-
-#[test]
-fn test_tile_to_string() {
-    let output = Tile {
-        id: "7a".to_string(),
-        name: Some("chequers".to_string()),
-        wall: false,
-        animation_frames: vec![
-            mocks::image::chequers_1(),
-            mocks::image::chequers_2(),
-        ]
-    }.to_string();
-
-    let expected = include_str!("../test/resources/tile-chequers").to_string();
-
-    assert_eq!(output, expected);
-}
-
 impl From<String> for Position {
     fn from(string: String) -> Position {
         // e.g. "2,5"
diff --git a/src/tile.rs b/src/tile.rs
new file mode 100644
index 0000000..3e07001
--- /dev/null
+++ b/src/tile.rs
@@ -0,0 +1,93 @@
+use crate::AnimationFrames;
+use crate::image::Image;
+use crate::mocks;
+
+#[derive(Debug, Eq, PartialEq)]
+pub struct Tile {
+    pub id: String, // base36 string
+    pub name: Option<String>,
+    pub wall: bool,
+    pub animation_frames: Vec<Image>,
+}
+
+impl From<String> for Tile {
+    fn from(string: String) -> Tile {
+        let mut lines: Vec<&str> = string.lines().collect();
+
+        let id = lines[0].replace("TIL ", "");
+
+        let last_line = lines.pop().unwrap();
+        let wall = match last_line == "WAL true" {
+            true => true,
+            false => {
+                lines.push(last_line);
+                false
+            }
+        };
+
+        let last_line = lines.pop().unwrap();
+        let name = match last_line.starts_with("NAME") {
+            true => Some(last_line.replace("NAME ", "").to_string()),
+            false => {
+                lines.push(last_line);
+                None
+            }
+        };
+
+        let animation_frames = lines[1..].join("");
+        let animation_frames: Vec<&str> = animation_frames.split("\n>\n").collect();
+        let animation_frames: Vec<Image> = animation_frames.iter().map(|&frame| {
+            Image::from(frame.to_string())
+        }).collect();
+
+        Tile { id, name, wall, animation_frames }
+    }
+}
+
+impl ToString for Tile {
+    #[inline]
+    fn to_string(&self) -> String {
+        format!(
+            "TIL {}\n{}{}{}",
+            self.id,
+            self.animation_frames.to_string(),
+            if self.name.as_ref().is_some() { format!("\nNAME {}", self.name.as_ref().unwrap())} else {"".to_string() },
+            if self.wall {"\nWAL true"} else {""}
+        )
+    }
+}
+
+#[test]
+fn test_tile_from_string() {
+    let output = Tile::from(include_str!("../test/resources/tile").to_string());
+
+    let expected = Tile {
+        id: "z".to_string(),
+        name: Some("concrete 1".to_string()),
+        wall: true,
+        animation_frames: vec![
+            Image {
+                pixels: vec![1; 64]
+            }
+        ],
+    };
+
+    assert_eq!(output, expected);
+}
+
+#[test]
+fn test_tile_to_string() {
+    let output = Tile {
+        id: "7a".to_string(),
+        name: Some("chequers".to_string()),
+        wall: false,
+        animation_frames: vec![
+            mocks::image::chequers_1(),
+            mocks::image::chequers_2(),
+        ]
+    }.to_string();
+
+    let expected = include_str!("../test/resources/tile-chequers").to_string();
+
+    assert_eq!(output, expected);
+}