Route 91 is a bus route operated by the Maryland Transit Administration in Baltimore. The line currently runs from Sinai Hospital to City Hall, serving the communities of Pimlico, Arlington, Walbrook, and Bolton Hill, Coppin State College and the corridors of Garrison Boulevard and Eutaw Place. The line has the second-highest farebox recovery rate of all MTA bus lines.
The bus route is the successor to the 16 Madison Avenue and 31 Garrison Boulevard streetcar lines.
Route 91 started operating in 1987 after being split from the long Route 19. It has followed essentially the same route throughout its lifetime since then, only with the modification of service operating via the Rogers Avenue Metro Subway Station full time. The line has faced various proposals for consolidation into other lines, but all have been fought.
The No. 31 Streetcar started operating in 1917. In 1952, it was absorbed by the No. 19 Streetcar, which in 1956 was converted to a bus. The no. 19 bus continued to operate from the Harford Road corridor to Garrison Boulevard for more than 30 years. The route was extended to Sinai Hospital when it absorbed the short lived Bus Route 90, which had operated from 1959 to 1960 between the Belvedere loop to Sinai.
In 1992, in conjunction with the opening of the Central Light Rail line, MTA proposed to eliminate Route 91 and provide the service on other routes, primarily Route 13. However, this plan was scrapped as a result of public outcry.
In 2005, as part of the Greater Baltimore Bus Initiative, a comprehensive overhaul plan for the region's transit system, MTA proposed once again to discontinue Route 91, and for the service to be absorbed by other routes, primarily by modifying Route 15 to Sinai Hospital. This plan was scrapped as a result of public outcry, especially because no bus service would have been provided on Eutaw Place in Bolton Hill.
In 2006, as part of phase II of GBBI, MTA proposed for Route 91 to remain on its current route at a reduced frequency, and for a new Route M-5 to operate from the Mt. Washington Light Rail Stop to Penn-North Metro Subway Station with overlapping service between Pimlico and Penn-North. Such a plan is yet to be implemented, and GBBI was canceled in 2007.