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 dark metal used in its construction was undefinable by Starfleet scanners, and had no match in the Federation database.