Liberty Tunnel Fan House

Katie Blackley / 90.5 WESA

Pittsburgh’s tunnels are considered the gateway to the city. More than 229,000 people drive through the Liberty, Fort Pitt, Squirrel Hill and Stowe tunnels each day.

Margaret J. Krauss / 90.5 WESA

It’s hard to miss the four brick stacks of the Liberty Tunnel Fan House towering over the houses on Secane Avenue in Mount Washington.

“There are two exhaust shafts,” said Bill Lester, Assistant Director of Construction for PennDOT’s District 11, pointing them out. “And there are two intake shafts where we draw fresh air in from up here. We push it down into the tunnel and then we turn around and we drag the bad air back out.”