The Dean Lindsey Memorial Tunnel underpass turns 35 years old on Sunday. The large structure opened in 1990 and is a part of the final mile of I-10.

According to the Arizona Department of Transportation, the tunnel serves more than 200,000 vehicles daily. It spans almost a mile between Third Street and Third Avenue.

ADOT also says the construction of the tunnel required heavy work. Workers placed 1,400 columns for bridge structure support and excavated a million cubic yards of soil.

Its current name comes from the civil engineer Dean Lindsey, who was heavily involved in interstate projects.

In 2021, a modern LED system replaced the tunnel’s sodium lighting.

The Deck Park Tunnel on Interstate 10 in Phoenix in 2024.

Arizona Department of Transportation

The Deck Park Tunnel on Interstate 10 in Phoenix in 2024.