md 170 was relocated as a road from md 176 north to what is now the md 170–md 162 junction in 1947 and 1948 to make way for the construction of friendship international airport. the highway's interchange with the friendship international airport access road, which was designated md 46 and later became i-195, was started in 1950, the same year the airport opened, and completed in 1954. south of the airport, md 170 ran concurrently with md 176 from the current md 176–md 652 intersection west to current md 170a, which the highway used to connect with the modern alignment of md 170. the stub of md 170 north from md 176 to friendship cemetery on the airport reservation became md 652. md 170 assumed its present alignment west of md 170a when the highway was relocated from md 176 south to the site of the md 100 interchange as the first carriageway of an ultimate divided highway between 1958 and 1960. the old alignment became much of current md 652 and the portion of md 652 north of md 176 was transferred to county maintenance.