diff --git a/lib/Travelynx.pm b/lib/Travelynx.pm
index 39eca59..64a1e85 100755
--- a/lib/Travelynx.pm
+++ b/lib/Travelynx.pm
@@ -1852,10 +1852,11 @@ sub startup {
 					: undef,
 				},
 				train => {
-					type => $status->{train_type},
-					line => $status->{train_line},
-					no   => $status->{train_no},
-					id   => $status->{train_id},
+					type    => $status->{train_type},
+					line    => $status->{train_line},
+					no      => $status->{train_no},
+					id      => $status->{train_id},
+					hafasId => $status->{extra_data}{trip_id},
 				},
 				intermediateStops => [],
 				visibility        => {
diff --git a/templates/api_documentation.html.ep b/templates/api_documentation.html.ep
index 0847139..9c9ee1f 100644
--- a/templates/api_documentation.html.ep
+++ b/templates/api_documentation.html.ep
@@ -63,6 +63,7 @@
 				"line" : "6", (Linie als String, nicht immer numerisch, ggf. null)<br/>
 				"no" : "30634", (Fahrtnummer als String, ggf. null oder leer)<br/>
 				"id" : "7512500863736016593" (IRIS- oder HAFAS-spezifische Fahrt-ID)<br/>
+				"hafasId" : "1|224479|0|80|30082023" (HAFAS-spezifische Fahrt-ID falls bekannt, ggf. null)<br/>
 			},<br/>
 			"visibility" : {<br/>
 				"desc": "private" / "unlisted" / "followers" / "travelynx" / "public",<br/>