Gas trunkline is a pipeline designed for natural gas transmission from production areas to consumption points. It is the main means of long-distance gas transmission. A gas trunkline is one of the main elements of the gas transmission system and the main component of the Russian Unified Gas Supply System (UGSS).

It is constructed of 720 to 1,420 millimeters steel pipes designed for 5.4 to 7.5 MPa operational pressures with the throughput of up to 30–35 billion cubic meters per annum. The gas trunkline laying can be: underground (0.8 to 0.1 meter depth to the upper pipe surface); overhead – on supports, onshore – in rock-fill dams. Submerged gas trunklines are constructed for gas transmission from offshore gas fields to the coast.