Harakka is situated in front of Kaivopuisto in the southernmost tip of Helsinki. Harakka hosts some toprope climbing and DWS. The toprope anchors can be difficult to rig sometimes. Long static ropes and some nuts are adviced.
For DWS you'll probably want to have a boat and you should check the water. There are some rocks under the water especially on the left side. The water depth is 4,0m once the sea level is zero. Logically, if the sea is low there is less water.
Harakka early season starts in February and lasts as long as it's possible to cross the water on ice. The ice can be thin so you should check the conditions and have the right gear before entering on ice. On a sunny winter day the rock is warm although the air temperature might be freezing. Afternoon sun shines on Harakka and the cliff dries very fast. The seepage is low to non-existent.