Interstate 695 encircles the city of Baltimore from Towson to the north to Dundalk and Glen Burnie to the south. The 51.5-mile loop constitutes a suburban route for most of its course north of I-95 and an industrial route to the south of I-95. 30.57 miles of the beltway are included within the Interstate system, while a 19.37 mile section, from Exit 33 south and west to Exit 4, are officially MD 695, but signed as I-695.3
Initial work on the Beltway commenced in 1951 on the stretch between MD 295 and MD 168 (Nursery Road). State officials took over the county-based project by 1953,3 and the beltway opened between Exits 4 and 7 and Exits 23 and 27 by 1958. During that same year, the beltway was designated Interstate 695.
Work on the beltway north of Interstate 95 was completed by July 1962. Construction on the route south of Interstate 95 would follow slowly under the designation of MD 695. The state route-based freeway opened between Exits 2 and 3 and Exits 35 and 39 by 1973. Completion of the route coincided with the opening of the Francis Scott Key Bridge on March 23, 1977.
Late 1990s and early 2000s projects focused on the expansion and modernization of the Baltimore Beltway. These projects involved widening the highway from six to eight lanes on the northern portion of the highway, expanding the two-lane section near Sparrows Point, and installing sound barriers throughout the route.
The Francis Scott Key Bridge, a continuous through truss bridge shaped with a steel arch, crosses the Patapsco River as it empties into Chesapeake Bay. Representing milepost zero for the beltway exit numbering system, the Key Bridge is tolled in both directions.