How to unlock and find the hidden bunker in ARC Raiders

The hidden bunker mode on the Spaceport map is a small mystery with a clear checklist, lock in four rooftop antennas, survive the ARCs that drop when you send each unlock signal, then track the unmarked entrance between the Fuel Lines and the Fuel Processing Area. This guide explains where the antennas commonly spawn, what you need to bring, and how to finish the terminal downloads once you’re inside.

Start by selecting the hidden bunker mode on Spaceport. Keep an eye on the minimap for four antenna icons. They change positions each match, but you will often see them on rooftops such as the Departure Building, Rocket Assembly, Control Tower, the North and South Trench Towers, Vehicle Maintenance, and the Shipping Warehouse.

For a better explanation, check out The Gaming Merchant’s full video guide.

Grab a zipline gadget before you drop in. The North and South Trench Towers require a zipline or the Trench Tower Key to reach the rooftop. Once you get a rooftop antenna, interact to establish the connection, stay nearby until it finishes, then interact again to send the unlock signal. Expect a swarm of ARCs right after you trigger each signal, so have medkits and ammo ready. If an antenna has already been used to send a signal, it will no longer appear on the map, so don’t waste time revisiting empty icons.

After all four signals are sent, you will get an on-screen notice that the hidden bunker is open, but the entrance is not marked for you. The entrance discovered by the Raiders sits between the Fuel Lines and the Fuel Processing Area. Watch for patrolling Bastions and Bombardiers around this zone and clear them before you try to enter.

Once inside the bunker, look for the terminals. Interact with a terminal to start a download, and stay right beside it until it completes. If you move away, the download will fail, the light will turn red, and you won’t be able to retrieve the data. Successful retrieval grants 500 XP for exploration. There are multiple terminals in the bunker. Theyre a decent XP source, and some players think they might be part of a larger puzzle that hasnt been solved yet. If youre chasing XP or want to speed up progression, pairing this run with the right skill choices helps – check our guide to the best Arc Raiders skills to unlock first for suggestions.

Need map context for Spaceport hotspots and rooftop access routes? See our breakdown of the best Arc Raiders maps for quests and items to plan your spawn and route before a hidden bunker attempt. Questions, tips, or a different bunker location to share? Drop a comment and follow us on X, Bluesky, and YouTube for more ARC Raiders guides.