Our Transportation segment operations generally consist of fee-based activities associated with transporting crude oil and NGL on pipelines, gathering systems, trucks and barges.

Revenue

Transportation revenue is generated through a combination of tariffs, pipeline capacity agreements and other transportation fees. The transportation segment also includes equity earnings from our investments in entities that own or are developing transportation assets including the Advantage, BridgeTex, Cactus II, Caddo, Capline, Cheyenne, Cushing Connect, Diamond, Eagle Ford, Midway, Saddlehorn, STACK, White Cliffs and Wink to Webster pipeline systems, as well as Settoon Towing.

Assets

As of December 31, 2019, Plains employed a variety of owned or leased long-term physical assets throughout the United States and Canada in the transportation segment, including approximately:

18,535 miles of active crude oil and NGL pipelines and gathering systems
35 million barrels of active, above-ground tank capacity used primarily to facilitate pipeline throughput and help maintain product quality segregation
50 transport and storage barges and 20 transport tugs through our interest in Settoon Towing
825 trailers (primarily in Canada)