diff --git a/channels/routing.py b/channels/routing.py
index 41ab0b0..0806bd5 100644
--- a/channels/routing.py
+++ b/channels/routing.py
@@ -141,7 +141,7 @@ class Route(object):
         """
         Returns the channel names this route listens on
         """
-        return self.channel
+        return {self.channel,}
 
     def __str__(self):
         return "%s %s -> %s" % (
@@ -204,7 +204,7 @@ class Include(object):
         """
         result = set()
         for entry in self.routing:
-            result.union(entry.channel_names())
+            result.update(entry.channel_names())
         return result
 
 
diff --git a/channels/tests/test_routing.py b/channels/tests/test_routing.py
index 5605175..bfc44cd 100644
--- a/channels/tests/test_routing.py
+++ b/channels/tests/test_routing.py
@@ -281,3 +281,24 @@ class RoutingTests(SimpleTestCase):
             consumer=consumer_2,
             kwargs={"version": "2", "room": "django"},
         )
+
+    def test_channels(self):
+        """
+        Tests that the router reports channels to listen on correctly
+        """
+        router = Router([
+            route("http.request", consumer_1, path=r"^/chat/$"),
+            route("http.disconnect", consumer_2),
+            route("http.request", consumer_3),
+        ])
+        # Initial check
+        self.assertEqual(
+            router.channels,
+            {"http.request", "http.disconnect"},
+        )
+        # Dynamically add route, recheck
+        router.add_route(route("websocket.receive", consumer_1))
+        self.assertEqual(
+            router.channels,
+            {"http.request", "http.disconnect", "websocket.receive"},
+        )