Maryland Route 157 is a state highway located in Baltimore County in the U.S. state of Maryland. The state highway runs 4.79 miles (7.71 km) from MD 158 in Sparrows Point north to North Point Road in Dundalk. MD 157 is an L-shaped highway serves as the primary highway through Dundalk and from Dundalk to Interstate 695 (I-695). The two highways to which MD 157 is assigned, Merritt Boulevard and Peninsula Expressway, were constructed as a four-lane divided county highway in the early 1960s. In the late 1960s, Merritt Boulevard was extended as ramps to I-695 that also serve MD 151 and MD 150. MD 157 was assigned to the highway in Sparrows Point in the early 1990s and extended through Dundalk to its present northern terminus in the late 1990s.

Maryland Route 156 is a state highway located in Harford County in the U.S. state of Maryland. Known as Aldino Road, the state highway runs 3.92 miles (6.31 km) from MD 22 near Churchville east to MD 155 near Hopewell Village. MD 156 provides access to the Harford County Airport in the unincorporated community of Aldino. The state highway, which was originally designated part of MD 155, was built as a modern highway by 1910 and rebuilt in the 1920s. MD 156 received its present designation in 1952 when MD 155 and MD 156 swapped paths.