The trick is the approach from the Fehrengsholz road. It doesn't seem to go any further there. But you can pass the courtyard (with the sign 'video surveillance') (next to the barrier) and then come into the grove and finally to the sea. Definitely dismount! Otherwise, the coarse gravel that the video monitor has scattered here will knock you off your bike. As I understand it, you can go through here (next to the barrier), at least I haven't found anything to the contrary.