Obelisk in Karlsruhe

Today we visited Karlsruhe, one of the big german cities in the Baden-W├╝rttemberg state. Before going there I read there has been some speculation about this city being used as a model for Washington, D.C. (since both cities have a centre from which the streets radiate). I couldn't stop thinking about this point when we were walking in the city center: When we passed by the Rondellplatz we observed this obelisk that might be in fact a model for the American one. Probably this city is very nice during the summer time, but today we realised the spring hasn't come yet to Karlsruhe because it was rainy, grey and cold ... brrrr.