This piece of history is on the market for $2,450,000 and comes with a remarkably clean backstory. Even if you haven't heard of Charles Carrollton, the guy that laid the cornerstone of the B&O Railroad, you have to admire the house he lived in. As a six bed, eight bath home it could feel large and unfriendly. But instead all that molding detail brings the rooms together in one uniform flow. It surely helps that it used to be the Mt. Vernon Institute for Young Ladies and Little Girls. You can almost hear the quaint footsteps of wholesome youngsters echoing off the walls. It is the only detached home on Mt. Vernon Square and a nearby carriage house is included in the sale.