It's more than 130 feet long and almost 30 feet wide and weighs 150 tons.
Latest news headlines:
It's called a superload and it's being moved today from Allegheny County to Ohio.
PennDOT says the cargo, a massive steel cone, will travel through parts of Allegheny, Butler, Clarion, Indiana, Jefferson, Mercer and Westmoreland counties.
Speeds will be slow: between 25 and 30 miles per hour and the superload will take up two traffic lanes.
That means stoppages and delays, but at what times is not known yet.
Affected routes in the Pittsburgh area include the Tri-Boro Expressway, William Penn Highway and Routes 130 and 48.
Full route includes: The load will begin travelling in Allegheny County on Routes 2037/Tri-Boro Expressway,130, 48, and 2048 North/William Penn Highway to Indiana County on Routes 22, 286, 129/Alpine Village Drive, 22 and 119 into Jefferson County continuing on Routes 436 and 36 to I-80 West in Brookville. The superload will then travel I-80 to the Ohio line.