Northside Trail is one of the longest, relatively flat hiking trails on Mount Tamalpais above 1,800 feet elevation. Its long (2.7 mile) forested single track, with north-facing lookout spots, provides hikers with lots to see and do. We recommend getting to Northside Trail by coming in off the top of Mount Tamalpais along Eldridge Grade. Alternatively, you can climb up to the eastern end of the trail by hiking out of Lake Lagunitas by way of Lakeview Road and climbing up Eldridge Grade.
Once at the trailhead, an old sign leads you into Northside Trail. Northside is a rugged trail, which contours east to west just under the ridge between the East and West Peaks of Mount Tam. Shady mixed dry forest of nutmeg, oak, manzanita are found as you cross north running ridges, with moister cool redwood trees tucked away near the springs in the canyons. This section of trail can be tough on the ankles with loose rock in long stretches of scree, so bring sturdy shoes.
A great spot for a break is at Colier Spring, where a old redwood bench is tucked between the trees and ferns next to the spring. Alice Eastwood, who was head botanist for the California Academy of Sciences for the first half of the 20th Century, called the spot "Butterfly Spring," because of the many species she found there. Colier Spring is also the junction of Upper Northside and Lower Northside Trails. When you are ready be sure to take signed Upper Northside Trail when you leave.
Upper Northside winds through the forest and then breaks out on a ridge of green serpentine. Here, stunted junipers, manzanita and others are scattered across the hostile rocky landscape. Catch International Trail to start the journey back up to the peaks.
You will eventually end on East Ridgecrest Road, where you go left for 20 feet and then catch Lakeview Trail (not the same as the one coming out of Lake Lagunitas), which climbs up to the top of Middle Peak. Be sure to take the side trek to the top for sweeping views before heading down the Middle Peak Fire Road and back to the East Peak Parking area. The East Peak parking area and visitors center has interpretative exhibits about the history of the mountain, and a snack shack for a well deserved treat.
Be sure to carry water, because there is none along the route.