The highest point of the city is at Kemnader Straße (Kemnader Street) in Stiepel at 196 metres above sea level; the lowest point is 43 metres at the Blumenkamp in Hordel.
The synagogue was set on fire and there was rioting against Jewish citizens.
The first Jews from Bochum were deported to Nazi concentration camps and many Jewish institutions and homes were destroyed. In December 1938, the Jewish elementary school teacher Else Hirsch began organising groups of children and adolescents to be sent to the Netherlands and England, sending ten groups in all.
The Ruhr tributaries are the Oelbach (where as well a waste water treatment plant is established), Gerther Mühlenbach, Harpener Bach, Langendreer Bach, Lottenbach, Hörsterholzer Bach and the Knöselbach.
The Ruhr in combination with upstream reservoirs is also used for drinking water abstraction.
Additional population gains came from immigration, primarily from Poland.