Napa/St. Helena -- The quieter northern end of the valley is an ideal place to rent a bicycle and ride the Silverado Trail. St. Helena Cyclery, 1156 Main St. (tel. 707/963-7736; www.sthelenacyclery.com), rents bikes for $10 per hour or $35 a day, including rear rack, helmet, lock, and bag in which you can pack a picnic.
Calistoga -- Cycling enthusiasts can rent bikes from Getaway Adventures/Wine Country Adventures (tel. 800/499-2453 or 707/568-3040; www.getawayadventures.com). Full-day group tours cost $149 per person, including lunch and a visit to four or five wineries, $195 per person for private groups of six or more. Bike rental without a tour costs $30 per day plus a $45 delivery fee to Napa Valley locations. You can also inquire about the company's kayaking and hiking tours.