Keystone XL and Rockies Express pipelines are the longest oil and gas pipelines in the United States as of 2015. Pipelines are the most economical way for companies to transport oil and gas from drilling sites to refineries.
TransCanada is constructing the 1,179-mile Keystone XL pipeline as of October 2015. The pipeline originates in Hardesty, Alberta, Canada and ends in Steele City, Nebraska. The pipeline will transport oil from the Western Canadian Sedimentary Basin and the Bakken.
The Rockies Express pipeline is 1,043 miles long and runs from the Colorado Rocky Mountains to eastern Ohio. The pipeline cost $5.6 billion to construct and can supply up to 16.5 billion cubic meters of natural gas per year.