In Far Cry 6, there are certain areas of the map that can be entered but are linked to the Operations Missions. Far Cry 6 is programmed in a way that doesn't let players easily explore locations they have no business being in yet. Unfortunately, some of these landmarks have Anti-Aircraft Cannons, which have containers of 50 Depleted Uranium. A few landmarks will be impossible to enter until the time is right, but some are easier to break into than others.