diff --git a/apps/web/src/App.tsx b/apps/web/src/App.tsx
index f93c40f..7e7ddf9 100644
--- a/apps/web/src/App.tsx
+++ b/apps/web/src/App.tsx
@@ -570,6 +570,7 @@ export function App() {
   );
 
   const clearRouteOutcome = useCallback(() => {
+    courseAssistant.stop();
     routeRequestId.current += 1;
     routeWeatherRequestId.current += 1;
     setRoute(null);
@@ -580,7 +581,20 @@ export function App() {
     setRouteWeatherError(null);
     setRouteWeatherLoading(false);
     setRouteLoading(false);
-  }, []);
+  }, [courseAssistant.stop]);
+
+  const editRoute = useCallback(() => {
+    clearRouteOutcome();
+    setPickMode(null);
+  }, [clearRouteOutcome]);
+
+  const cancelRoute = useCallback(() => {
+    setRouteStart(null);
+    setDestination(null);
+    setWaypoints([]);
+    clearRouteOutcome();
+    setPickMode(null);
+  }, [clearRouteOutcome]);
 
   const saveCurrentBoat = useCallback((profile: BoatProfile) => {
     const stored = persistBoatProfile(profile);
@@ -675,11 +689,12 @@ export function App() {
       return;
     }
 
+    courseAssistant.stop();
     setRoute(selected);
     if (activeVesselProfile) {
       loadRouteWeather(selected, activeVesselProfile);
     }
-  }, [activeVesselProfile, loadRouteWeather, routeOptions]);
+  }, [activeVesselProfile, courseAssistant.stop, loadRouteWeather, routeOptions]);
 
   const clearStart = useCallback(() => {
     setRouteStart(null);
@@ -716,6 +731,7 @@ export function App() {
   }, [clearRouteOutcome]);
 
   const loadOfflineVoyage = useCallback((voyage: OfflineVoyage) => {
+    courseAssistant.stop();
     routeRequestId.current += 1;
     routeWeatherRequestId.current += 1;
     setRouteStart(voyage.plan.start);
@@ -737,7 +753,7 @@ export function App() {
     if (voyage.plan.vesselProfile && navigator.onLine) {
       loadRouteWeather(offlineRoute, voyage.plan.vesselProfile);
     }
-  }, [loadRouteWeather]);
+  }, [courseAssistant.stop, loadRouteWeather]);
 
   const uiMode = anchorWatch.phase !== "idle"
     ? "anchor"
@@ -1022,6 +1038,8 @@ export function App() {
                 onClearDestination={clearDestination}
                 onUseGpsAsStart={useGpsAsStart}
                 onSelectRoute={selectRouteOption}
+                onEditRoute={editRoute}
+                onCancelRoute={cancelRoute}
                 guidanceActive={courseAssistant.active}
                 onStartGuidance={startCourseAssistant}
                 onEditBoat={() => {
diff --git a/apps/web/src/components/MapView.tsx b/apps/web/src/components/MapView.tsx
index abe84ac..f798869 100644
--- a/apps/web/src/components/MapView.tsx
+++ b/apps/web/src/components/MapView.tsx
@@ -417,8 +417,8 @@ export function MapView({
       map.addSource("route-guidance", {
         type: "geojson",
         data: guidanceFeatures(
-          guidanceActiveRef.current ? positionRef.current : null,
-          guidanceActiveRef.current ? guidanceTargetRef.current : null
+          routeRef.current && guidanceActiveRef.current ? positionRef.current : null,
+          routeRef.current && guidanceActiveRef.current ? guidanceTargetRef.current : null
         )
       });
       map.addSource("anchor-watch", {
@@ -950,13 +950,18 @@ export function MapView({
 
   useEffect(() => {
     const map = mapRef.current;
-    if (!map?.isStyleLoaded()) {
+    const source = map?.getSource("route-guidance") as GeoJSONSource | undefined;
+    if (!source) {
       return;
     }
 
-    const source = map.getSource("route-guidance") as GeoJSONSource | undefined;
-    source?.setData(guidanceFeatures(guidanceActive ? position : null, guidanceActive ? guidanceTarget : null));
-  }, [guidanceActive, guidanceTarget, position]);
+    source.setData(
+      guidanceFeatures(
+        route && guidanceActive ? position : null,
+        route && guidanceActive ? guidanceTarget : null
+      )
+    );
+  }, [guidanceActive, guidanceTarget, position, route]);
 
   useEffect(() => {
     const map = mapRef.current;
@@ -987,42 +992,45 @@ export function MapView({
 
   useEffect(() => {
     const map = mapRef.current;
-    if (!map?.isStyleLoaded()) {
+    const source = map?.getSource("start-point") as GeoJSONSource | undefined;
+    if (!source) {
       return;
     }
 
-    const source = map.getSource("start-point") as GeoJSONSource | undefined;
-    source?.setData(startPoint ? pointFeature(startPoint) : emptyPoint());
+    source.setData(startPoint ? pointFeature(startPoint) : emptyPoint());
   }, [startPoint]);
 
   useEffect(() => {
     const map = mapRef.current;
-    if (!map?.isStyleLoaded()) {
+    const source = map?.getSource("destination") as GeoJSONSource | undefined;
+    if (!source) {
       return;
     }
 
-    const source = map.getSource("destination") as GeoJSONSource | undefined;
-    source?.setData(destination ? pointFeature(destination) : emptyPoint());
+    source.setData(destination ? pointFeature(destination) : emptyPoint());
   }, [destination]);
 
   useEffect(() => {
     const map = mapRef.current;
-    if (!map?.isStyleLoaded()) {
+    const source = map?.getSource("waypoints") as GeoJSONSource | undefined;
+    if (!source) {
       return;
     }
 
-    const source = map.getSource("waypoints") as GeoJSONSource | undefined;
-    source?.setData(waypointFeatures(waypoints));
+    source.setData(waypointFeatures(waypoints));
   }, [waypoints]);
 
   useEffect(() => {
     const map = mapRef.current;
-    if (!map?.isStyleLoaded()) {
+    if (!map) {
+      return;
+    }
+    const source = map.getSource("route") as GeoJSONSource | undefined;
+    if (!source) {
       return;
     }
 
-    const source = map.getSource("route") as GeoJSONSource | undefined;
-    source?.setData(route ? routeFeature(route) : emptyLine());
+    source.setData(route ? routeFeature(route) : emptyLine());
     fitRouteOnMap(map, route);
   }, [route]);
 
diff --git a/apps/web/src/components/RoutePlanner.tsx b/apps/web/src/components/RoutePlanner.tsx
index 3a6afa4..a56700d 100644
--- a/apps/web/src/components/RoutePlanner.tsx
+++ b/apps/web/src/components/RoutePlanner.tsx
@@ -93,6 +93,8 @@ type RoutePlannerProps = {
   onClearDestination: () => void;
   onUseGpsAsStart: () => void;
   onSelectRoute: (routeId: string) => void;
+  onEditRoute?: () => void;
+  onCancelRoute?: () => void;
   guidanceActive?: boolean;
   onStartGuidance?: () => void;
   onEditBoat?: () => void;
@@ -148,6 +150,8 @@ export function RoutePlanner({
   onClearDestination,
   onUseGpsAsStart,
   onSelectRoute,
+  onEditRoute = () => undefined,
+  onCancelRoute = () => undefined,
   guidanceActive = false,
   onStartGuidance = () => undefined,
   onEditBoat = () => undefined,
@@ -612,13 +616,29 @@ export function RoutePlanner({
         </section>
       )}
 
-      <button
-        className="secondary-action"
-        type="button"
-        onClick={() => setPlannerView("input")}
-      >
-        Plan ändern
-      </button>
+      <div className="route-plan-actions">
+        <button
+          className="secondary-action"
+          type="button"
+          onClick={() => {
+            onEditRoute();
+            setPlannerView("input");
+          }}
+        >
+          Plan ändern
+        </button>
+        <button
+          className="secondary-action route-cancel-action"
+          type="button"
+          onClick={() => {
+            onCancelRoute();
+            setPlannerView("input");
+          }}
+        >
+          <X size={15} aria-hidden="true" />
+          Route verwerfen
+        </button>
+      </div>
 
       {result && (
         <section className="course-assistant-launch" aria-label="Navigation starten">
diff --git a/apps/web/src/styles/app.css b/apps/web/src/styles/app.css
index adec154..d19f96d 100644
--- a/apps/web/src/styles/app.css
+++ b/apps/web/src/styles/app.css
@@ -1029,6 +1029,20 @@ button:disabled {
   font-weight: 800;
 }
 
+.route-plan-actions {
+  display: grid;
+  grid-template-columns: repeat(2, minmax(0, 1fr));
+  gap: 8px;
+}
+
+.route-plan-actions > button {
+  width: 100%;
+}
+
+.route-cancel-action {
+  color: #8b3528;
+}
+
 .route-result[data-severity="ok"] {
   background: #dceee6;
   color: #196f5c;
diff --git a/apps/web/tests/map-view.test.tsx b/apps/web/tests/map-view.test.tsx
index a8faa3c..049e239 100644
--- a/apps/web/tests/map-view.test.tsx
+++ b/apps/web/tests/map-view.test.tsx
@@ -28,6 +28,7 @@ vi.mock("maplibre-gl", () => {
     layerDefinitions = new globalThis.Map<string, any>();
     renderedFeatures: any[] = [];
     zoom = 13;
+    styleLoaded = true;
     container: HTMLElement;
     fitBounds = vi.fn(() => this);
     easeTo = vi.fn(() => this);
@@ -110,7 +111,7 @@ vi.mock("maplibre-gl", () => {
     }
 
     isStyleLoaded() {
-      return true;
+      return this.styleLoaded;
     }
 
     getZoom() {
@@ -553,6 +554,128 @@ describe("MapView marine feature information", () => {
     );
   });
 
+  it("atomically replaces and clears route drawings while other map data is loading", async () => {
+    const stableOnPickCoordinate = vi.fn();
+    const stableOnMapReady = vi.fn();
+    const firstRoute: RouteResult = {
+      id: "first",
+      name: "Hauptroute",
+      geometry: {
+        type: "LineString",
+        coordinates: [
+          [7.1, 53.1],
+          [7.2, 53.2],
+          [7.3, 53.3]
+        ]
+      },
+      distanceNm: 10,
+      eta: null,
+      warnings: [],
+      dataSources: [],
+      routingMode: "fairway"
+    };
+    const secondRoute: RouteResult = {
+      ...firstRoute,
+      id: "second",
+      name: "Alternative 1",
+      geometry: {
+        type: "LineString",
+        coordinates: [
+          [8.1, 54.1],
+          [8.2, 54.2],
+          [8.3, 54.3],
+          [8.4, 54.4]
+        ]
+      }
+    };
+    const view = render(
+      <MapView
+        config={config}
+        position={{ lat: 53.1, lon: 7.1 }}
+        accuracyM={5}
+        startPoint={{ lat: 53.1, lon: 7.1 }}
+        destination={{ lat: 53.3, lon: 7.3 }}
+        waypoints={[{ lat: 53.2, lon: 7.2 }]}
+        pickMode={null}
+        route={firstRoute}
+        guidanceActive
+        guidanceTarget={{ lat: 53.2, lon: 7.2 }}
+        onPickCoordinate={stableOnPickCoordinate}
+        onMapReady={stableOnMapReady}
+      />
+    );
+    await act(async () => maplibreState.current.emit("load"));
+
+    const routeSource = maplibreState.current.sources.get("route");
+    const guidanceSource = maplibreState.current.sources.get("route-guidance");
+    const startSource = maplibreState.current.sources.get("start-point");
+    const destinationSource = maplibreState.current.sources.get("destination");
+    const waypointSource = maplibreState.current.sources.get("waypoints");
+    maplibreState.current.styleLoaded = false;
+
+    view.rerender(
+      <MapView
+        config={config}
+        position={{ lat: 54.1, lon: 8.1 }}
+        accuracyM={5}
+        startPoint={{ lat: 54.1, lon: 8.1 }}
+        destination={{ lat: 54.4, lon: 8.4 }}
+        waypoints={[{ lat: 54.3, lon: 8.3 }]}
+        pickMode={null}
+        route={secondRoute}
+        guidanceActive
+        guidanceTarget={{ lat: 54.2, lon: 8.2 }}
+        onPickCoordinate={stableOnPickCoordinate}
+        onMapReady={stableOnMapReady}
+      />
+    );
+
+    expect(routeSource.setData).toHaveBeenLastCalledWith({
+      type: "Feature",
+      properties: {},
+      geometry: secondRoute.geometry
+    });
+
+    view.rerender(
+      <MapView
+        config={config}
+        position={{ lat: 54.1, lon: 8.1 }}
+        accuracyM={5}
+        startPoint={null}
+        destination={null}
+        waypoints={[]}
+        pickMode={null}
+        route={null}
+        guidanceActive={false}
+        guidanceTarget={null}
+        onPickCoordinate={stableOnPickCoordinate}
+        onMapReady={stableOnMapReady}
+      />
+    );
+
+    expect(routeSource.setData).toHaveBeenLastCalledWith({
+      type: "Feature",
+      properties: {},
+      geometry: { type: "LineString", coordinates: [] }
+    });
+    expect(guidanceSource.setData).toHaveBeenLastCalledWith({
+      type: "FeatureCollection",
+      features: []
+    });
+    expect(startSource.setData).toHaveBeenLastCalledWith({
+      type: "FeatureCollection",
+      features: []
+    });
+    expect(destinationSource.setData).toHaveBeenLastCalledWith({
+      type: "FeatureCollection",
+      features: []
+    });
+    expect(waypointSource.setData).toHaveBeenLastCalledWith({
+      type: "FeatureCollection",
+      features: []
+    });
+  });
+
   it("focuses a route event requested by the shared navigation workspace", async () => {
     const stableOnMapReady = vi.fn();
     const view = render(
@@ -636,7 +759,14 @@ describe("MapView marine feature information", () => {
         startPoint={{ lat: 52, lon: 7 }}
         destination={{ lat: 52, lon: 7.1 }}
         pickMode={null}
-        route={null}
+        route={{
+          geometry: { type: "LineString", coordinates: [[7, 52], [7.1, 52]] },
+          distanceNm: 4,
+          eta: null,
+          warnings: [],
+          dataSources: [],
+          routingMode: "fairway"
+        }}
         guidanceActive
         guidanceTarget={{ lat: 52.001, lon: 7.01 }}
         onPickCoordinate={vi.fn()}
diff --git a/apps/web/tests/route-planner.test.tsx b/apps/web/tests/route-planner.test.tsx
index 02ea1e8..53c9992 100644
--- a/apps/web/tests/route-planner.test.tsx
+++ b/apps/web/tests/route-planner.test.tsx
@@ -383,6 +383,7 @@ describe("RoutePlanner", () => {
   });
 
   it("opens the compact result view and keeps critical warnings above secondary route details", () => {
+    const onEditRoute = vi.fn();
     const result = {
       ...routeOption("primary", "Hauptroute", 4),
       warnings: [
@@ -411,6 +412,7 @@ describe("RoutePlanner", () => {
         onClearDestination={vi.fn()}
         onUseGpsAsStart={vi.fn()}
         onSelectRoute={vi.fn()}
+        onEditRoute={onEditRoute}
         onCollapse={vi.fn()}
       />
     );
@@ -422,9 +424,44 @@ describe("RoutePlanner", () => {
     expect(screen.queryByRole("button", { name: "Start auf Karte setzen" })).not.toBeInTheDocument();
 
     fireEvent.click(screen.getByRole("button", { name: "Plan ändern" }));
+    expect(onEditRoute).toHaveBeenCalledTimes(1);
     expect(screen.getByText("Route planen")).toBeVisible();
     expect(screen.getByRole("button", { name: "Start auf Karte setzen" })).toBeVisible();
-    expect(screen.getByRole("button", { name: "Zur Route" })).toBeVisible();
+  });
+
+  it("explicitly discards a planned route through the parent state", () => {
+    const onCancelRoute = vi.fn();
+    const result = routeOption("primary", "Hauptroute", 4);
+
+    render(
+      <RoutePlanner
+        startPoint={{ lat: 52, lon: 7 }}
+        gpsPosition={null}
+        destination={{ lat: 52, lon: 7.1 }}
+        result={result}
+        routeOptions={[result]}
+        weatherReport={null}
+        weatherLoading={false}
+        weatherError={null}
+        loading={false}
+        error={null}
+        pickMode={null}
+        onSubmit={vi.fn()}
+        onPickStart={vi.fn()}
+        onPickDestination={vi.fn()}
+        onClearStart={vi.fn()}
+        onClearDestination={vi.fn()}
+        onUseGpsAsStart={vi.fn()}
+        onSelectRoute={vi.fn()}
+        onCancelRoute={onCancelRoute}
+        onCollapse={vi.fn()}
+      />
+    );
+
+    fireEvent.click(screen.getByRole("button", { name: "Route verwerfen" }));
+
+    expect(onCancelRoute).toHaveBeenCalledTimes(1);
+    expect(screen.getByText("Route planen")).toBeVisible();
   });
 
   it("filters retired fairway and depth warnings from route results", () => {