The tunnel runs for 2,160 feet (660 m)[1][3] under College Hill on Providence's East Side, with its east portal at Thayer Street, the busy commercial district near Brown University, leading to its west portal at North Main Street near the Rhode Island School of Design.

[5][6] The west portal of the tunnel was built directly under the Waterman Building (1893), the original classroom and museum gallery structure of the Rhode Island School of Design.

Extensive and complex construction methods were required to support the building as the tunnel was bored underneath it.

[3]: 92 In 2018, US Senator Jack Reed (RI-D) toured the tunnel with RIPTA officials, and announced a $903,000 federal grant for planning repairs and improvements to the heavily-used transit structure.

[7] The Waterman Building (1893) of the Rhode Island School of Design is visible directly above the west portal openings.