There is a crowded swimming hole to the very north of the CCC Camp area, north of the Kids Area.
There are are additional swimming lakes south and a bit east of the camp area easily reachable by bicycle. To get there, take the pedestrian & bike path leading south towards Zehdenick from the roundabout in front of the Team Harbor area. The first lake that you will encounter on your left is the Döbertstich, which is within reasonable walking distance. There are additional lakes further to the south that you will want a bicycle to get to.
For a prettier option that doesn’t require you to walk much or have a bicycle, Team Harbor provides a 5 minutes water taxi service to cross the Havel river from Neuer Hafen to the quiet lake located on the other side. Your group must have a DECT phone to call for the water taxi back.
If you are looking for some even nicer places to swim, we recommend either the crystal clear Großer Kuhwallsee (about 7 nautical miles NE of the harbor along the Havel river, requires a boat or dinghy to get there and is not easily accessible by bicycle) or the Prerauer Stich, which is south along the Havel river and to the east, just before you get to Zehdenick harbor.
Prerauer Stich can be quickly reached by dinghy and, with a bit of a detour through Zehdenick, by bicycle.