Image: Bend Studio / PlayStationOfficial screenshot from Bend Studio / PlayStation.
Belknap is the volcanic region south of the Cascade, home to Ada Tucker's Hot Springs camp and the town of Marion Forks. You come here early for Tucker's work and stay for its seven Hordes and three infestations.
Hot Springs is your base in Belknap, and every job here pays into Tucker's Trust and credits. Marion Forks sits on the river with the Old Wagon Hotel, a church and a NERO burial pit nearby. The Belknap Caves were a Ripper hideout and hold a story Horde.
Belknap is volcanic country, with lava rock and craters between the roads. Fast travel only works along routes with no live infestation, so burning the nests here opens the map up.
Skip Belknap if you need mushrooms for Herbology, since none grow here. Hot Springs credits only spend at Hot Springs, so finish its trust levels before you rely on its gear.
Marion ForksMarion Forks is an abandoned riverside town in Belknap, split by a blown bridge. It has a church, two motels and a NERO burial pit above it. It matters to Deacon, and it holds an infestation, a Horde and good early loot.Cascade
Cascade is the northern starting region, in the Farewell wilderness around Copeland's Camp at Peaceful Lake. It is where you learn the game, and it still has 8 Hordes and 4 NERO research sites to come back for.
Crater Lake
Crater Lake is the far southern region built around the real lake and Wizard Island, the Militia's headquarters. It opens in the second half of the story and has the most encampment jobs and NERO research sites in the game.
Highway 97
Highway 97 is the southern stretch of US highway running through Chemult and past Chemult Community College. It has more Hordes than any other region, including the 300-strong Lobert Draw Ridge Horde, so bring your best gear.
Iron Butte
Iron Butte is the Rippers' home territory in the east, locked until late in the story. Come here for its 11 R.I.P. Sermons, two Ripper ambush camps, the Rogue Tunnel checkpoint and the Cloverdale research facility.