If you’re ever driving along the 101 around King City (why the hell would anyone be doing that?) you should take an hour detour to Arroyo Seco River. There’s this great hike that’s part swimming and part hopping over boulders. There are these great sections of carved out lagoons with 50 foot rock faces and swims through canyons so narrow that you can touch both sides. The whole thing took us about 7 hours with periodic breaks for food and shade. I recommend bringing a dry bag and some water shoes for the mixed conditions.
On a side note, King City sounds like a rad place for a rock venue, roller derby team, or strip club. Unfortunately all I found was a Motel 6 and a Taco Bell.