This is for the parkour enthusiasts out there. There's a certain achievement, Spider Assassin, actually, which calls on the player to climb the entirety of the Hagia Sophia in under 25 seconds. Think you're up to it? The reward is 20G for Xbox 360 players, or a bronze trophy for PlayStation 3 players.
YouTuber PowerPyx shows you how to do it. And it couldn't be more straight forward than this, folks. So boot up your consoles, and get to climbing!