Route 27 is a bus route operated by the Maryland Transit Administration in Baltimore. The line currently runs from the Reisterstown Plaza Metro Subway Station in northwest Baltimore to Port Covington in South Baltimore through downtown. The line also serves the communities of Pimlico, Mt. Washington, Cross Keys, Hampden, and Cherry Hill, and the Greyhound bus terminal. The bus route is the successor to the 10 Roland Park, 12 Westport, and 25 Mount Washington streetcar lines.

Mount Washington is an area of northwest Baltimore, Maryland. It is a designated city historic district and divided into two sections: South Road/Sulgrave to the southeast and Dixon's Hill to the north. The Mount Washington Historic District was listed on the National Register of Historic Places in 1990 with a boundary increase in 2001, with five contributing buildings and four contributing structures.