The Jumpman Zone is a set of custom-built maps, challenges, and rewards that exists separately from the main Fortnite map. So if you’re looking for it on the map, you’re going to be looking for a very long time, and you’re never going to find it.
To access the Jumpman zone, you need to enter the following Island Code: 5519-3138-2454. This will take you to a snowy wilderness decorated by gigantic crystalline basketballs and basketball hoops. There are also six small portals here. Each portal will take you to a different map on which you must complete a Quest in order to earn a pair of shoes. The shoes, in turn, unlock VIP rooms (or MVP rooms), which are accessed via the larger portals in the Jumpman Zone.
Each VIP room contains trickshot challenges, and you need to complete all of these in order to get more rewards. You don’t actually have to get the ball through the hoops. Just hitting the hoops is enough. Each level of the trickshot challenge has a different gameplay twist, but they’re all pretty straightforward. Just make sure you read the signs to find out what you need to do each time. Congratulations! You are now the Michael Jordan of Fortnite.