Getting into Iraq from Turkey is pretty quick - a few stamps, a few questions, a complimentary cup of tea from the Kurdish border post, and you're in.
Going the other direction, on the other hand, is a nightmare. It took almost four hours to cross, with about ten different stops, each operating in a different and entirely opaque way. The most interesting was the Turkish secret police, where extremely smooth-talking, fluent English speakers comb through bags looking for evidence of involvement with Kurdish nationalists.
This photo was taken from the bridge over the river Habur (a tributary of the Tigris, which runs just a few miles to the west), looking back at Iraq from the Turkish side.