Among (many) other things, this is where foreigners have to go in order to extend their visas. At least, that was the case in 2005. I read in the papers at the time that the Mogamma was going to be closed and its offices divided among several buildings in a new administrative center (with computers instead of the double-thick ledgers that were in use). Of course, I liked that fact.
Services could take so long (and the lines could be even longer) that there is concession service from uniformed waiters in the hallways. A wonderfully rich and convoluted experience, but not for the faint of heart, claustrophobic or those short on time or patience. See this Washington Post story (
www.washingtonpost.com/wp-dyn/content/article/2005/09/2... or this Egyptian tourism page (
www.touregypt.net/featurestories/mugamma.htm).