According to the route, we should turn right and smash into that building... Then after 30 minutes of tunnelling, walk along the river and into the water...

The truth is this is entirely possible. The building has an opening right at the location when we are supposed to smash into it. This is not visible from satellite image. Let's see what happens about the water-treading part.

At a later date, we went hiking. We were laden with worries, a sorrowful figure in a cheerful scene. The water was still or more precisely piecewise linear. The reflected world was cut into broad shards. We had all the time to ourselves to think about what we should do. We kept walking until suddenly a bridge appeared. It looked that there was no need to walk into the river after all.