Maryland Route 161 (MD 161) is a state highway in the U.S. state of Maryland. The state highway runs 5.38 mi from MD 155 in Hopewell Village north to U.S. Route 1 (US 1) in Darlington. MD 161 connects Havre de Grace with Susquehanna State Park and northeastern Harford County. The state highway was mostly constructed in the late 1920s and early 1930s.
Susquehanna State Park is in Harford County.
By the statement it is hard to tell rather the park is in Hartford County. I imagine it was hard to tell for the system because both places are in the statement.