Ther is a tunnel at the Inn at Spanish Head.
We used the tunnel that is parking for the Inn at Spanish Head which takes you to their hotel. It is steps away from the RV park on the same side. Once you've left the tunnel there are signs that direct you to the beach which is a short walk along 101. We enjoyed the beach at Roads End which is a short drive from the RV park (Logan Rd) but get there early as parking fills up fast.
If I remember right the resort recommends driving down and parking near the beach. There's a big parking lot near Kyllo's restaurant that we parked at but there are probably other spots elsewhere. The Inn at Spanish Head is right across 101 with beach access but unfortunately they don't allow non-guests through there.
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