"Blood and silver is what flow through Markarth." You may hear this from one of the locals, it is one hundred percent true. The city is corrupt and debase, relying on its prisoners in Cidhna Mine to make all it's money, while violently censoring rumors of the Forsworn. If you wish to enter this cesspool of greed and lies, the map below will assist you.
Image borrowed from elderscrolls.wikia.com