These four hikes will leave you foot-sore, leg-weary and flush with the satisfaction of knowing you can handle the roughest routes routes through the Bay Area's toughest terrain.
Many of these trails go up and down old ranch roads built for motorized travel, adding to the difficulty and making them even more enticing for those who can't resist a daunting challenge. Note that three of the four are in the East Bay's Diablo Range, far from the cooling breezes of the coast and the gentle shade of the redwoods.
Speaking of redwoods, the Berry Creek Falls Loop at Big Basin Redwoods State Park is not nearly as arduous as its East Bay brethren, but it simply could not be left off any list of the region's best strenuous hikes.
These treks are not recommended if you've never gone more than five miles, but they should be within reach of experienced endurance athletes.
Best time to go: Spring wildflower season (March to mid-May).
Worst time to go: mid- to late summer, when the dry heat makes all-day outings pretty much unthinkable.
What to bring:
Food/water for an all-day outing (taking a water filter or purifier is highly recommended).
Clothing in layers. Note if you go in winter, it can be windy and bitterly at the highest elevations of the East Bay parks.