No, as the gate is locked.
Reservations are for tours, and can be made at recreation.gov. Tours happen Tuesday, Thursday, and Saturday from 10 am to 12 pm. During the summers tours happen additionally on Mondays and Fridays 10 am to 12 pm. All tours begin at the former Piedras Blanca's Motel, approx 1.5 miles north of the actual light station grounds.
No. You are not allowed in unless you have a reservation (make online). Then the gate is opened and you are allowed to drive in.
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