Hummelsee

Even if the name of the nearby Müllberg is a deterrent for many:
The water quality of the Hummelssee is checked regularly and is safe for bathing. It is a true jewel in a relatively short distance to the center and is always worth a quick refreshment.

In the 1960s, a sand and gravel pit was created in the Hummelsbüttler Feldmark. In the early 1970s, more sand pits were added. After the end of dredging, the pits were filled, d. H. used as landfill. One of the pits remained partially open. The area concerned was the basis for the formation of the bumblebee.
Update 5.12.19: the water level of the lake is quite low. It's time for a lot of rain.
(Source: Wikipedia)

The lake is a real gem and very well nestled between Raakmoor and Glashütter Moor. You can include him in many tours. The Duvenstedter Brook is also not far away. But please do not make the mistake to drive to the Glashütte highway. There is neither bike nor footpath. Rehagen or Tegelsbarg are much better.
Not to be underestimated is the view from the "garbage mountains" phenomenal in good weather! Incidentally, the picture in the avatar was created there.

Nice place to start a tour to Raakmoor (for example).

The lake is located directly on the garbage mountain and is best seen from up there.