The Alaska Pipeline

The pipeline runs 800 miles through the interior of Alaska to transport crude oil from Prudhoe Bay in the North to the port in Valdez. 

This shows the pig- a bullet shaped pipe cleaner that they send through to clean the inside of the pipe where paraffin and other stuff builds up.

At this point the pipeline is above ground. It's about half above and half below ground. These sections were designed so they could cross the unstable permafrost.