Gateways were circular in shape, and were usually found placed on a platform or in a wall. The size varied, but most were large enough for a person to walk through. While inactive, the gateway resembled a perfect ring, with a empty clear center that looked like the opening of a tunnel that does no exist. When activated, by pressing a button on one side, the gate would open, to a kawoosh sound, revealing a swirling vortex in the center of ring that resembled liquid magma.
The original purpose behind the Gateways was lost when the Oppressors disappeared. However, many have speculated over what that purpose could be.
Some primitive species who encountered them thought that they were doorways to other realms or different dimensions. Others thought that they were prisons, designed to trap dangerous individuals.
- The Gateways, in appearance, were inspired by the Stargate franchise.