Look past the big-box stores along I-880 to discover Union City’s necklace of wild open space

A tour of the best parks in this underrated city southeast of San Francisco can be done on an almost totally flat 20-mile bike ride, starting and ending at the Union City BART station.

A good deal of it follows the Alameda Creek Regional Trail, where you’ll enjoy natural scenery and not have to contend with traffic.

Almost half of the route is through open space and regional park land. Some beginning portions are on city streets, and one section in Coyote Hills Regional Park is a gravel trail, but it’s ridable even on a touring bike.

Moderately fit riders can complete this route in a day, but you’ll want to start early and bring water, trail snacks, sunglasses, sunscreen, and biker’s gloves.

MAP: Download a map of the Union City area, including parks and the Alameda Creek Regional Trail.

For a full itinerary on where to go and what to see in Union City:  Plan a day trip to Union City

MILES 0–6.75

Union City BART station to Coyote Hills Regional Park via the Alameda Creek Regional Trail: From the Union City BART station, hang a left on Decoto Road. In 1 mile, just after Royal Ann Drive, cross the bridge to pick up the paved Alameda Creek Regional Trail, making a right turn onto it. After a bit, the trail crosses under I-880 to more open space. Continue until you reach mile marker .05, where you turn left onto the steep, dirt Red Hill Trail to enter Coyote Hills. Download a detailed map of the trails at Coyote Hills Regional Park.

MILES 6.75–9.25

Coyote Hills park entrance to Nectar Garden and marshlands: Once you enter Coyote Hills, follow signs to the Bayview Trail. After a short climb, the trail levels off across the side of a hill and in less than a mile, you’ll be at the Coyote Hills visitor center, where you can take a breather at the Nectar Garden. Across the street from the visitor center, enter the marshlands on the gravel trail (bikes are not allowed on the boardwalks). You’ll soon hit Chochenyo Trail. Take it to the right and you’ll pick up the D.U.S.T. Trail, which will lead you back to the Alameda Creek Regional Trail.

MILES 9.25–12.25

Alameda Creek Regional Trail to Cam Huong: Cycle back the way you came on the Alameda Creek Regional Trail, and turn off on Alvarado Road (it’s marked on the overpass). Cross the bridge to head left and in 0.8 mile, you’ll hit Cam Huong, where you can pick up sandwiches, in a strip mall at Galaxy Drive. $; 32124 Alvarado Blvd.; 510/441-0590.

MILES 12.25–18.5

Cam Huong to Dry Creek Garden: Take Alvarado Boulevard back to the Alameda Creek Regional Trail and continue east toward Decoto Road. Pick up Decoto Road again and head back the way you came, northeast toward the Union City BART station. Follow Decoto Road past BART and out to Mission Boulevard. After turning left on Mission, May Road is your first right, and at the road’s end (just a few hundred feet in), you’ll find Dry Creek Garden.

MILES 18.5–20

Dry Creek Garden to BART: You’ve got only about a mile left to go, and it’s all flat. Hang a left on Mission Boulevard as you exit the garden on May Road. Then make a right at Decoto Road. Go straight for several blocks before making a left at Union Square where you’ll find the BART station.

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