We prefer dry camping in the area, but will advise with hookups in mind. For Lassen, I would stay at Rancheria RV Park. Centrally located to visit both Burney Falls and Lassen Park. After heading to the coast on hwy 299, I would stay at Mad River Rapids RV park in Arcata and use that as a home base for a day trip south to the "Avenue of the Giants". I would then head north on hwy 101 with the trailer and stop along the old highway adjacent to Prairie Creek State Park and do some hiking (good lunch break too). I would then stay at the KOA near Crescent City and take a day trip to Jedediah Smith State Park. The pier in Crescent City is pretty neat too, if your into the fishing fleet stuff.