At this position (51.390526935920406, 7.1742972700361305) you have to drive under an old railway bridge to get from Hattingen (Germany) to Langenberg.
The bridge has a clearance height of 4m for trucks,
but is incorrectly marked as 3.1m in the HERE maps:
Therefore, the route is calculated awkwardly and unnecessarily around the supposed obstacle (A difficult path for trucks) instead of just straight ahead.