u/JustBrowsing-1216

Random question of the day.

I was driving on the Mass Pike heading west and when I got to the Prudential Tunnel I noticed doors along the right side of the road. Some were ground level, which doesn't seem odd, but there were quite a few at loading dock level. What are these for? Are they remnants of something else or do they have some specific purpose?

Link to map for an example: https://maps.app.goo.gl/gvh2xquFSsjTT3SN6

Just curious, figured I'd ask!