The Armstrong Tunnel in Pittsburgh, Pennsylvania, connects Second Avenue at the South Tenth Street Bridge

South Tenth Street Bridge

South Tenth Street Bridge, most often called the Tenth Street Bridge, but officially dubbed the Philip Murray Bridge, is a suspension bridge spanning the Monongahela River in Downtown Pittsburgh, Pennsylvania...

, under the Bluff where Duquesne University

Duquesne University

Duquesne University of the Holy Spirit is a private Catholic university in Pittsburgh, Pennsylvania, United States. Founded by members of the Congregation of the Holy Spirit, Duquesne first opened its doors as the Pittsburgh Catholic College of the Holy Ghost in October 1878 with an enrollment of...

 is located, to Forbes Avenue

Forbes Avenue

Forbes Avenue is one of the longest streets in Pittsburgh, Pennsylvania, United States. It has a length of about ten miles and is named for General John Forbes , whose expedition recaptured Fort Duquesne and who renamed the place Pittsburgh in 1758.The westernmost terminus of Forbes Avenue lies at...

 between Boyd Street and Chatham Square.

Construction

The tunnel was constructed between 1926 and 1927. The chief engineer was Vernon R. Covell of the Allegheny County Public Works Department. The tunnel portals were designed by a city architect, Stanley L. Roush, who is also is noted for the Smithfield Street Bridge

Smithfield Street Bridge

The Smithfield Street Bridge is a lenticular truss bridge crossing the Monongahela River in Pittsburgh, Pennsylvania, USA.The bridge was designed by Gustav Lindenthal, the engineer who later designed the Hell Gate Bridge. The bridge was built between 1881–83, opening for traffic on March 19, 1883....

 portals, the City-County Building, the Corliss Tunnel, and many other municipal projects.

Characteristics

The tunnel itself is characterized by twin bores of horseshoe cross-section, and bends halfway through. It also has a pedestrian walkway on the western side. Pghbridges.com

Pghbridges.com

Pghbridges.com is a reference site created by Bruce S. Cridlebaugh. Formally titled, Bridges and Tunnels of Allegheny County and Pittsburgh, PA, pghbridges.com has information on many of the structures of the area...

 reports that since the air draft flows toward the river, bicyclists are able to travel through the tunnel in that direction "with little or no effort."

A legend mentioned by the site involves a notion that the bend in the tunnel was a mistake, and whoever was responsible committed suicide

Suicide

Suicide is the act of intentionally causing one's own death. Suicide is often committed out of despair or attributed to some underlying mental disorder, such as depression, bipolar disorder, schizophrenia, alcoholism, or drug abuse...

 in shame. Chief engineer Covell did not kill himself, invalidating this legend. Author Bruce S. Cridlebaugh suspects the bend was related to mines or other geological factors, property rights (including Duquesne University), or alignments with existing or proposed roads.

Name

The tunnels were named in honor of Joseph G. Armstrong

Joseph G. Armstrong

Joseph G. Armstrong was born in what is today the Northside neighborhood of the U.S. city of Pittsburgh. He became a glassmaker and eventually participated in the glass union and labor movement. From his labor connections he was elected to City Council and then ran successfully for County Coroner...

, County Director of Public Works. Most of the bridges over the Pittsburgh's three rivers were replaced between 1910 and 1940, years which included Mr. Armstrong's terms as Mayor of Pittsburgh and Allegheny County Commissioner.