8x3 parkour is a 24-stage map slightly based on MCC's Parkour Warrior. There are 8 themed areas (red desert, coral, jungle, mountains, space, city, ice, hell). The map also has a jukebox feature at the beginning, so you can listen to music discs while you parkour if you want. There's also a hint book which tries to explain the best way to do each section.
The rules are explained at the beginning of the map but basically: play in adventure, make sure you stand on the pressure plates to get checkpoints and don't interact with the trapdoors (treat them like iron trapdoors).
The checkpoint system wont work in multiplayer, but otherwise the map is perfectly functional in multiplayer.