Starting point was around center of this screenshot. Distance was 1000 meters, so, I think that distance along the river left coast shoud be approximately 1000 meters also.
And only bridge awailable is railway, not accessible by foot.
I think that right coast shoud not be awailable at all.
Also, there is a fence, marked by red line, so street at left (north to south direction) is not available also. If i try to create a route from the same point to any point at this street, I can see that only two routes exists.
full graphhopper response:
iso.geojson (211.0 KB)