Abstract: A method in which large-volume gas containers, for example, airships having a gas holding capacity of, for example, 400,000 m3, can be filled with a process gas, includes first completely filling the container with an auxiliary gas, the density of which differs from that of the process gas. The process gas is then quiescently introduced into an upper area of the gas container in such a way that no significant mixing with the air occurs and, at the same time, the auxiliary gas is removed by suction from the lower area of the gas container. To purify the contents of the gas container, purified or fresh process gas is quiescently introduced into the upper area of the gas container in such a way that no significant mixing with the contaminated process gas present in the gas container. At the same time, the contaminated process gas is removed by suction from the lower area of the gas container. To empty the gas container, the above-described process is reversed.