The hook
After winter rain, a creek off Mount Tamalpais tumbles down a mossy fern-walled staircase in waterfall after waterfall — the most beloved cascade hike in Marin, and it looks like a rainforest most people don't know California has.
01Why it's worth it
Cataract Creek drops off Mt Tam's flank toward Alpine Lake through a slot of coast redwood, tanoak, and bay laurel so densely mossed and ferned that on a foggy post-rain day the whole gorge seems lit from within. The trail rises alongside it on stone and wood steps past a chain of falls — not one big drop but a sequence, each bend revealing another cascade over dark rock — which is exactly why Marin locals rate it their favorite waterfall walk with genuine, repeated affection. It's rain-fed and honest about it: gorgeous and roaring December through April, a quiet trickle by summer. The tradeoff is the climb (steep, rugged, ~1,000 feet in three miles) and, at the popular lower trailhead, a real crowd on the first sunny weekend after a storm — but the payoff per step in the wet season is among the best in the Bay Area.
02How to experience it
Cataract trailhead on Bolinas-Fairfax Road just south of Alpine Dam (roadside parking; fills fast after rain — the Rock Spring trailhead off Ridgecrest is the quieter approach from above). Go within a few days of real rain, wear grippy shoes for wet stone, and turn around at the falls unless you want the full 8-mile loop. Pairs with Bon Tempe's lakes right next door.