Learn how the Trans-Alaska Pipeline was conceived and built in the 1970s in this video segment adapted from AMERICAN EXPERIENCE. When oil was discovered in northern Alaska's Prudhoe Bay, the challenge facing engineers was how to transport it to refineries outside of Alaska. Engineers developed plans for a north–south pipeline that, unlike other pipelines, would be built aboveground due to the pervasive ice-rich soil layer called permafrost. The pipeline cut through the Alaskan landscape, causing much contention, especially among Alaska Native peoples and environmentalists.