As the crow flies Skyrim isn't much larger than Cyrodiil, but all the tall mountains and rolling hills make the province feel much larger than it actually is. Cyrodiil didn't have mountains right in the middle of the province so getting from, say, Cheydinhal to Chorrol takes a shorter time than traveling a distance roughly equal in Skyrim, say, from Dawnstar to Windhelm, because you have to navigate either over or around a mountain range to get there. I like this.