Whisking down scenic Mount Tamalpais on a mountain bike is a sweet reward for cyclists who climb to the top of Marin's iconic 2,571-foot peak. The classic route to the top is the eight-mile-long Old Railroad Grade fire road from Mill Valley to Tam's East Peak.

Suitable for intermediate riders (the road is rocky in places), the fire road never exceeds a 6% grade thanks to the Mill Valley & Mount Tamalpais Scenic Railway. The railway was a tourist train known as "the Crookedest Railroad in the World" that built the route and operated from 1896 to 1929.

The ride starts just 11 miles north of San Francisco at the fire road's trailhead in Mill Valley's redwood-shaded Blithedale canyon. It winds up to paved Summit Road before entering the park and rising up the mountain's southern flank numerous twists and turns, and wide-open stretches doused in full sun and shady forest of redwood, oak and bay trees.

At the historic West Point Inn, you can refill water and take a breather on the Inn's shady veranda before continuing the climb to Tam's East Peak for stunning views of the Pacific, San Francisco Bay and southern Marin lands.

Then the fun begins as the twisting and turning thrill ride spirits you back down to Mill Valley, an invigorating half-day ride on Marin's enchanting Mount Tamalpais.

Contact the Marin Bicycle Coalition for detailed information on bike trails.