View of Phoenixsee from Neuer Kaiserberg

An originally unplanned landfill offers the best view of the entire PHOENIX Lake. It is named after the neighboring Kaiserberg Neuer Kaiserberg, Kaiserberg II or also Phoenixsee-Halde. The (old) Kaiserberg is a natural hill and has been partially dismantled over time. Excess excavated soil from the lake is stored here on the new landfill.

Kaiserberg is an artificial hill providing a great viewpoint across Dortmund Hoerde about 40 m above Phoenix lake, created 2006-2010 when heavy metal contaminated soils were excavated from the former Phoenix steel mill site there. Contaminated soil was buried inside the hill such that inhabitants should not come in contact under 'normal conditions'. Contaminants can wash into groundwater; the lake has no exit and is fed by groundwater. Swimming is not allowed. Phosphate filtering and other lake maintenance costs close to a million Euro per year. Besides Kaiserberg the contaminated soil was also spread about 50 cm under the terraces for the 2000 new housing units, and about 1/5th was deposited on the Phoenix West area nearby.
Kaiserberg and the lake attract events with hundreds of participants and daily hikers/bikers on and around the water throughout the year.
de.wikipedia.org/wiki/Phoenix-See#Sanierung_des_Bodens

After the end of the extremely successful art and culture festival Emscherkunst 2016, the Dortmund PHOENIX See finally got its first permanent cultural retreat. At the so-called Kaiserberg - the large landscaped building in the extreme northeast of the area - a small but fine sculpture park was unveiled at the beginning of September.