The Trans-Alaska Pipeline took $8 billion and two years to build. It is one of the most difficult engineering feats of all time. The pipeline is 800 miles long and has a diameter of four feet. The zigzagging pipeline carries crude oil from 250 miles north of the Arctic Circle to the terminal at Valdez. It crosses three mountain ranges, 34 major waterways, and 800 small streams. The oil travels at 5.4 mph and takes 6.2 days to travel the whole pipeline.

More on the Alaskan Pipeline