Well what can one say about the area? It is simply the only stone worth a boulder around Hamburg. Definitely worth for some fun at the beach and I guess there are little spots where you can watch a such a nice harbor skyline when bouldering.
You can use the ferry 62 from "Landungsbrücken" to "Neumühlen". By car, approach via highway "A7" and leave at exit Othmarschen (No. 29) then merge onto "Walderseestraße" and at its end turn into "Reventlowstraße". Continue straight until "Elbchausee" and park you car here. You can walk through "Schröders Park" to "Hans-Leip Ufer"