Completed in 1874, it carried freight and passenger trains between the Eads Bridge and the rail yards in the Mill Creek Valley, bypassing busy downtown streets.

[4] At that time, many railroads did not have licenses to operate in Missouri and the company eventually defaulted on its debts and a federal court appointed J.P. Morgan and Solon Humphreys as receivers.

[8] In 1889, Jay Gould was instrumental in the creation of the Terminal Railroad Association of St. Louis (TRRA), who took ownership of the bridge and tunnel.

In 1992, just east of the present day Convention Center station, a portion of the tunnel beneath Washington Avenue and Broadway collapsed, injuring no one.

[12] That spring, Metro began rehabilitating the Downtown Tunnel, including three of its stations: 8th & Pine, Convention Center, and Laclede's Landing.

Its foundations are made up primarily of Aux Vases sandstone while the upper portion of the tunnel is constructed of brick barrel vaults.

[2] In the subway stations that were cut into the tunnel, the ends of the platforms are met with brick archways that complement the arch motif used throughout the MetroLink system.