A few things:
- The 4-laning and limited access on Route 4 predates the Beltway. It was considered a more important route than Suitland Parkway, especially considering there were long-range plans at the time for a freeway upgrade of Route 4 from what is now the Beltway to Upper Marlborough.
Correct. The four lane MD-4 came to a halt at what is now the signals at Dower House Road in 1964 (
many crashes here over the years -
this needs to be an interchange). For reasons not clear, in 1964 the four lanes resumed at the old half interchange at Ritchie Marlboro Road (former MD-221).
Also, the Suitland Parkway was onlu widened to four lane divided from MD-4 to MD-458 (Silver Hill Road) in the early 1990's. Before that, it was two lanes undivided using what are now the outbound lanes. The grading work for the inbound lanes was done when the parkway was built, but there was no subgrade or anything else.
- Route 4 is too close to Suitland Parkway to have interchanges at both. Route 4 was deemed more important.
Correct. Also consider that prior to the NMSL in 1973, the posted limit here on I-495 was
70 MPH.
- More important than having a Suitland Parkway interchange at the Beltway would be a Suitland interchange at Forestville Rd.
Also remember that the primary reason for building the Suitland Parkway was to provide federal road access to and from D.C. to what was then Andrews AFB.
not the Capital Beltway.