diff --git a/TODO.md b/TODO.md
index f1ea820..5af828c 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,6 +1,4 @@
-[cps] [subway] `defineStation`
-
-[cps] [subway] `defineLine` -- take a ordered list of stations
+[cps] [subway] `defineLine` -- take an ordered list of stations
 
 [cps] [subway] define `bostonSubway`
 
diff --git a/src/cps/subway/Subway.ts b/src/cps/subway/Subway.ts
index 8c1a886..12ca818 100644
--- a/src/cps/subway/Subway.ts
+++ b/src/cps/subway/Subway.ts
@@ -1,7 +1,7 @@
 export type LineId = string
 export type StationId = string
 
-export type Position = string
+export type Position = { x: number; y: number }
 
 export type Line = {
   id: LineId
@@ -27,3 +27,12 @@ export function createSubway(name: string): Subway {
     stationMap: new Map(),
   }
 }
+
+export function defineStation(
+  subway: Subway,
+  stationId: StationId,
+  lineIds: Array<LineId>,
+  position: Position,
+): void {
+  ///
+}
diff --git a/src/cps/subways/bostonSubway.ts b/src/cps/subways/bostonSubway.ts
index dfe57ca..73754af 100644
--- a/src/cps/subways/bostonSubway.ts
+++ b/src/cps/subways/bostonSubway.ts
@@ -1,4 +1,4 @@
-import { createSubway } from "../subway/index.js"
+import { createSubway, defineStation } from "../subway/index.js"
 
 export const bostonSubway = createSubway("boston-subway")
 
@@ -7,20 +7,23 @@ export const bostonSubway = createSubway("boston-subway")
 // defineLine(bostonSubway, "orange-line")
 // defineLine(bostonSubway, "blue-line")
 
-// defineStation(bostonSubway, "airport", ["blue-line"], 4.0, 1.0))
-// defineStation(bostonSubway, "aquarium", ["blue-line"], 3.75, 0.1))
-// defineStation(bostonSubway, "wood-island", ["blue-line"], 5.0, 2.0))
-// defineStation(bostonSubway, "state", ["blue-line", "orange-line"], 3.1, -0.75))
+// prettier-ignore
+{
+  defineStation(bostonSubway, "airport", ["blue-line"], {x: 4.0, y: 1.0})
+  defineStation(bostonSubway, "aquarium", ["blue-line"], {x: 3.75, y: 0.1})
+  defineStation(bostonSubway, "wood-island", ["blue-line"], {x: 5.0, y: 2.0})
+  defineStation(bostonSubway, "state", ["blue-line", "orange-line"], {x:3.1, y:-0.75})
 
-// defineStation(bostonSubway, "park-street", ["green-line", "red-line"], 2.5, -0.5))
-// defineStation(bostonSubway, "government-center", ["green-line", "blue-line"], 2.9, -0.25))
-// defineStation(bostonSubway, "copley-square", ["green-line",], 1.0, -1.0))
-// defineStation(bostonSubway, "boston-u", ["green-line",], -1.0, -1.0))
-// defineStation(bostonSubway, "north-station", ["green-line", "orange-line"], 2.5, 0.75))
-// defineStation(bostonSubway, "haymarket", ["orange-line" "green-line",], 2.75, 0.5))
+  defineStation(bostonSubway, "park-street", ["green-line", "red-line"], {x: 2.5, y:-0.5})
+  defineStation(bostonSubway, "government-center", ["green-line", "blue-line"], {x:2.9,y: -0.25})
+  defineStation(bostonSubway, "copley-square", ["green-line",], {x:1.0, y: -1.0})
+  defineStation(bostonSubway, "boston-u", ["green-line",], {x:-1.0, y:-1.0})
+  defineStation(bostonSubway, "north-station", ["green-line", "orange-line"], {x:2.5, y:0.75})
+  defineStation(bostonSubway, "haymarket", ["orange-line" ,"green-line",], {x: 2.75, y:0.5})
 
-// defineStation(bostonSubway, "south-station", ["red-line"], 3.0, -1.0)
-// defineStation(bostonSubway, "washington", ["red-line", "orange-line"], 2.75, -0.75)
-// defineStation(bostonSubway, "kendall-square", ["red-line"], 1.0, 0.0)
-// defineStation(bostonSubway, "central-square", ["red-line"], -1.0, 0.0)
-// defineStation(bostonSubway, "harvard-square", ["red-line"], -2.0, 1.0)
+  defineStation(bostonSubway, "south-station", ["red-line"], {x: 3.0, y:-1.0})
+  defineStation(bostonSubway, "washington", ["red-line", "orange-line"], {x:2.75, y:-0.75})
+  defineStation(bostonSubway, "kendall-square", ["red-line"], {x:1.0, y:0.0})
+  defineStation(bostonSubway, "central-square", ["red-line"], {x:-1.0, y:0.0})
+  defineStation(bostonSubway, "harvard-square", ["red-line"], {x:-2.0, y:1.0})
+}