diff --git a/test/db.js b/test/db.js
index 2c963efd..214ce9d0 100644
--- a/test/db.js
+++ b/test/db.js
@@ -21,6 +21,7 @@ const testJourneysStationToPoi = require('./lib/journeys-station-to-poi')
 const testEarlierLaterJourneys = require('./lib/earlier-later-journeys')
 const journeysFailsWithNoProduct = require('./lib/journeys-fails-with-no-product')
 const testDepartures = require('./lib/departures')
+const testJourneysWithDetour = require('./lib/journeys-with-detour')
 
 const isObj = o => o !== null && 'object' === typeof o && !Array.isArray(o)
 
@@ -159,15 +160,12 @@ test('journeys: via works – with detour', co(function* (t) {
 		passedStations: true
 	})
 
-	validate(t, journeys, 'journeys', 'journeys')
-
-	const leg = journeys[0].legs.some((leg) => {
-		return leg.passed && leg.passed.some((passed) => {
-			return passed.station.id === württembergallee
-		})
+	yield testJourneysWithDetour({
+		test: t,
+		journeys,
+		validate,
+		detourIds: [württembergallee]
 	})
-	t.ok(leg, 'Württembergalle is not being passed')
-
 	t.end()
 }))
 
diff --git a/test/insa.js b/test/insa.js
index 6387bd0b..af3ca98e 100644
--- a/test/insa.js
+++ b/test/insa.js
@@ -16,6 +16,7 @@ const testJourneysStationToPoi = require('./lib/journeys-station-to-poi')
 const testEarlierLaterJourneys = require('./lib/earlier-later-journeys')
 const journeysFailsWithNoProduct = require('./lib/journeys-fails-with-no-product')
 const testDepartures = require('./lib/departures')
+const testJourneysWithDetour = require('./lib/journeys-with-detour')
 
 const isObj = o => o !== null && 'object' === typeof o && !Array.isArray(o)
 
@@ -123,18 +124,12 @@ test('journeys: via works – with detour', co(function* (t) {
 		passedStations: true
 	})
 
-	validate(t, journeys, 'journeys', 'journeys')
-
-	const leg = journeys[0].legs.some((leg) => {
-		return leg.passed && leg.passed.some((passed) => {
-			return (
-				passed.station.id === '8010077' || // todo: trim IDs
-				passed.station.id === dessau
-			)
-		})
+	yield testJourneysWithDetour({
+		test: t,
+		journeys,
+		validate,
+		detourIds: ['8010077', dessau] // todo: trim IDs
 	})
-	t.ok(leg, 'Dessau is not being passed')
-
 	t.end()
 }))
 
diff --git a/test/lib/journeys-with-detour.js b/test/lib/journeys-with-detour.js
new file mode 100644
index 00000000..2358a898
--- /dev/null
+++ b/test/lib/journeys-with-detour.js
@@ -0,0 +1,21 @@
+'use strict'
+
+const co = require('./co')
+
+const testJourneysWithDetour = co(function* (cfg) {
+	const {test: t, journeys, validate, detourIds} = cfg
+
+	// We assume that going from A to B via C *without* detour is currently
+	// impossible. We check if the routing engine computes a detour.
+
+	validate(t, journeys, 'journeys', 'journeys')
+
+	const leg = journeys[0].legs.some((leg) => {
+		return leg.passed && leg.passed.some((passed) => {
+			return detourIds.includes(passed.station.id)
+		})
+	})
+	t.ok(leg, detourIds.join('/') + ' is not being passed')
+})
+
+module.exports = testJourneysWithDetour
diff --git a/test/oebb.js b/test/oebb.js
index fc92c581..10e9ec2e 100644
--- a/test/oebb.js
+++ b/test/oebb.js
@@ -20,6 +20,7 @@ const testJourneysStationToPoi = require('./lib/journeys-station-to-poi')
 const testEarlierLaterJourneys = require('./lib/earlier-later-journeys')
 const journeysFailsWithNoProduct = require('./lib/journeys-fails-with-no-product')
 const testDepartures = require('./lib/departures')
+const testJourneysWithDetour = require('./lib/journeys-with-detour')
 
 const when = createWhen('Europe/Vienna', 'de-AT')
 
@@ -150,18 +151,12 @@ test('journeys: via works – with detour', co(function* (t) {
 		passedStations: true
 	})
 
-	validate(t, journeys, 'journeys', 'journeys')
-
-	const leg = journeys[0].legs.some((leg) => {
-		return leg.passed && leg.passed.some((passed) => {
-			return (
-				passed.station.id === donauinsel ||
-				passed.station.id === donauinselPassed
-			)
-		})
+	yield testJourneysWithDetour({
+		test: t,
+		journeys,
+		validate,
+		detourIds: [donauinsel, donauinselPassed]
 	})
-	t.ok(leg, 'Donauinsel is not being passed')
-
 	t.end()
 }))
 
diff --git a/test/vbb.js b/test/vbb.js
index b9751308..e1f6d79c 100644
--- a/test/vbb.js
+++ b/test/vbb.js
@@ -26,6 +26,7 @@ const testJourneysStationToPoi = require('./lib/journeys-station-to-poi')
 const testEarlierLaterJourneys = require('./lib/earlier-later-journeys')
 const journeysFailsWithNoProduct = require('./lib/journeys-fails-with-no-product')
 const testDepartures = require('./lib/departures')
+const testJourneysWithDetour = require('./lib/journeys-with-detour')
 
 const when = createWhen('Europe/Berlin', 'de-DE')
 
@@ -251,15 +252,12 @@ test('journeys: via works – with detour', co(function* (t) {
 		passedStations: true
 	})
 
-	validate(t, journeys, 'journeys', 'journeys')
-
-	const leg = journeys[0].legs.some((leg) => {
-		return leg.passed && leg.passed.some((passed) => {
-			return passed.station.id === württembergallee
-		})
+	yield testJourneysWithDetour({
+		test: t,
+		journeys,
+		validate,
+		detourIds: [württembergallee]
 	})
-	t.ok(leg, 'Württembergalle is not being passed')
-
 	t.end()
 }))