Park on the bluff at South Carlsbad State Beach and stay put for the week. The campground sits three miles south of the village on Carlsbad Boulevard, on a bare cliff straight over the Pacific, and sites release on a rolling six-month window at 8 a.m. Pacific on ReserveCalifornia. Book the site first and the van second, and count on 7 consecutive nights as the ceiling from March through November.
After that the only real decision is which side of the park road you want. The ocean row is the one people picture and it is also completely bare, no shade at any hour, with four stairways dropping to a narrow surf beach. The inland row trades the view for trees and a two-minute walk. Motorhomes and trailers top out at 35 feet on either side, so anything longer is a different park and a look at RVs across California.
The gate is worth reading twice before you drive it, because no freeway exit lands you in the park. Come off I-5 at Poinsettia Lane, run west to the coast road, turn north, and take the legal U-turn at the Breakwater Road light to come back down to the entrance on your right.
Carlsbad State Beach, the village, and the lagoon
Carlsbad State Beach, the in-town strand locals call Tamarack, is a day stop and stays one. It runs along Carlsbad Boulevard at Tamarack Avenue with a paved seawall above the sand and warm-water jetties at the south end, close enough to the village to reach on a bike. Surf it, eat in town, drive back down the coast to sleep.
Late winter and spring, the Flower Fields at Carlsbad Ranch open the terraced ranunculus rows above the freeway, a block of color you can pick out from I-5. Buy a ticket, give it a couple of hours, and park in their lot like everyone else.
For a slower morning, the north-shore trail at Batiquitos Lagoon runs 2.7 miles along a tidal estuary. It is open dawn to dusk and unlit, so it is not an after-dinner walk in winter.
Farther up and down the coast
The bluffs keep going in both directions. South, the state-beach camping picks up again through Cardiff and Encinitas on the way into San Diego. North across the Orange County line, San Onofre's surf breaks ride with the San Clemente run, and Crystal Cove's coves with Costa Mesa. Turn inland instead and it is wine country, which the Temecula lander picks up.