diff --git a/docs/control-ui.md b/docs/control-ui.md
index e8db8707e..89d24b7b1 100644
--- a/docs/control-ui.md
+++ b/docs/control-ui.md
@@ -8,8 +8,7 @@ read_when:
 
 The Control UI is a small **Vite + Lit** single-page app served by the Gateway under:
 
-- `http://<host>:18789/` (preferred)
-- `http://<host>:18789/ui/` (legacy alias)
+- `http://<host>:18789/`
 
 It speaks **directly to the Gateway WebSocket** on the same port.
 
diff --git a/src/config/config.ts b/src/config/config.ts
index 4d84d8316..4047d3742 100644
--- a/src/config/config.ts
+++ b/src/config/config.ts
@@ -102,7 +102,7 @@ export type CanvasHostConfig = {
 };
 
 export type GatewayControlUiConfig = {
-  /** If false, the Gateway will not serve the Control UI (/, /ui/). Default: true. */
+  /** If false, the Gateway will not serve the Control UI (/). Default: true. */
   enabled?: boolean;
 };
 
diff --git a/src/gateway/control-ui.ts b/src/gateway/control-ui.ts
index c722de89b..db4a60dd9 100644
--- a/src/gateway/control-ui.ts
+++ b/src/gateway/control-ui.ts
@@ -87,10 +87,8 @@ export function handleControlUiHttpRequest(
 
   const url = new URL(urlRaw, "http://localhost");
 
-  if (url.pathname === "/ui") {
-    res.statusCode = 302;
-    res.setHeader("Location", "/");
-    res.end();
+  if (url.pathname === "/ui" || url.pathname.startsWith("/ui/")) {
+    respondNotFound(res);
     return true;
   }
 
@@ -106,7 +104,6 @@ export function handleControlUiHttpRequest(
 
   const rel = (() => {
     if (url.pathname === ROOT_PREFIX) return "";
-    if (url.pathname.startsWith(UI_PREFIX)) return url.pathname.slice(UI_PREFIX.length);
     if (url.pathname.startsWith("/assets/")) return url.pathname.slice(1);
     return url.pathname.slice(1);
   })();