Gauntlet track

Gauntlet track or interlaced track (also gantlet track) is an arrangement in which railway tracks run parallel on a single track bed and are interlaced (i.e. overlapped) such that only one pair of rails may be used at a time. Since this requires only slightly more width than a single track, all rails can be carried on the same crossties/sleepers. Trains run on the discrete pair of rails appropriate to their direction, track gauge or loading gauge.