Underneath 3rd Street

There's been a lot of construction on 3rd Street between Market and Chestnut lately, mostly beneath the surface of the street, replacing sanitary sewer lines and other utilities. Given that the block sits squarely in the oldest part of the city, with the block probably among the first inhabited in the city, there's a lot going on underground. All the recent work lets us take a peek at everything that's happening beneath our feet.