Interstate 195 (I-195) is an auxiliary Interstate Highway in the US state of Maryland. The highway runs from I-95 in Arbutus east to Maryland Route 170 (MD 170) near the Baltimore/Washington International Airport (BWI Airport) in Linthicum. I-195, which is also known as Metropolitan Boulevard, is the main connection between the airport terminal and highways leading to Baltimore, Washington DC, and Annapolis, including I-95, MD 295, and I-97. The interchange with MD 170, which forms part of the Airport Loop, provides access to various airport-related services. I-195 also links I-95 with Catonsville and the University of Maryland, Baltimore County (UMBC), via a westward continuation of Metropolitan Boulevard that is part of MD 166. I-195 was constructed in three sections. The first section was a connection between MD 295 and the airport. This segment was built as Maryland Route 46 (MD 46) and completed in 1951 shortly after the opening of the airport, which was originally named Friendship International Airport. The second segment was completed at the opposite end of the highway in the mid-1970s, connecting US Route 1 (US 1) and I-95 with MD 166 and UMBC. The first two segments were connected when the portion between MD 295 and US 1 was constructed in the late 1980s. The whole length of the highway was completed and was marked as I-195 in 1990. In 2015, the eastern terminus was cut back from the airport to MD 170, with the former section between those two points becoming MD 995A. Route description I-195 begins at the western edge of its interchange with I-95. The freeway continues west as MD 166, which has a partial interchange for UMBC Boulevard, which leads to the UMBC campus, before ending next to a park-and-ride facility at Rolling Road, on which MD 166 continues north toward Catonsville. The I-95 interchange is a partial cloverleaf that has flyover ramps from northbound I-95 to westbound I-195 and from southbound I-95 to eastbound I-195. I-195 heads southeast as a four-lane freeway with a speed limit of across CSX Transportation's Baltimore Terminal Subdivision railroad line and meets US 1 at a four-ramp partial cloverleaf interchange. The highway crosses over I-895 (Harbor Tunnel Thruway) with no access and curves south on a viaduct to cross the Patapsco River, where the freeway passes from Baltimore County to Anne Arundel County, and Amtrak's Northeast Corridor railroad line, which also carries MARC Train's Penn Line.