The Bankhead Tunnel in Mobile will reopen Friday night after it closed for five days for upgrades, the Alabama Department of Transportation said.

The tunnel is expected to open no later than 8 p.m. Friday, according to an ALDOT release.

The tunnel closed Monday morning to allow for upgrades to the tunnel’s electrical and lighting systems, as well as installation of a new emergency generator.

Throughout the closure, motorists have been directed to take alternate routes, including the Wallace Tunnel or the Africatown Bridge.

Construction of the Bankhead Tunnel began in 1938 and it opened to traffic for the first time in 1941, according to the University of South Alabama archives. It was built at a cost of $4 million — $65 million in today’s dollars.

It is named for John Hollis Bankhead, who served in both houses of the Alabama legislature and later as a U.S. Senator. He was also the grandfather of Hollywood legend Tallulah Bankhead.

When it opened, the tunnel cut 7 1/2 miles off the distance from Mobile to the eastern shore of Mobile Bay. On opening day, Feb. 20, 1941, bicycles and pedestrians were — for the only time ever — allowed to go through the tunnel.

ALDOT says the new generator is one part of what will be ongoing electrical upgrades.