On an ordinary Tuesday, Old Mill Park looks like the calmest six acres in Mill Valley. Redwoods shade the picnic tables, a dog walker cuts through toward Cascade Drive, a couple of kids climb on the old mill wheel near the creek. Nothing about the scene suggests that this same patch of ground, bounded by Throckmorton Avenue and Old Mill Street, is the busiest piece of public land in town.
But look at the city's own event calendar and a different picture emerges. Between June and Thanksgiving weekend, Old Mill Park and the trailhead it sits beside do the work of a festival ground, a finish line, a starting gun, an aid station, and a staging area for an ultramarathon, sometimes all within the same six weeks. Most residents feel the traffic and the parking shuffle without ever connecting it to a single cause. The cause is one park, asked to do five or six jobs a year.
One Park, Six Jobs a Year
The pattern shows up clearly if you line up the dates. In 2025, the city's calendar recorded the Dipsea Race using the downtown plaza and Old Mill Park's race route on June 8, the Double Dipsea using a turn-around point and aid station on August 23, the Escape from Alcatraz Triathlon starting its Dipsea Race portion on September 14, the Mill Valley Fall Arts Festival occupying the park September 20 and 21 (with setup beginning the Tuesday before and breakdown running through the following Monday), the Zero Breast Cancer Dipsea Hike/Run starting and finishing there October 4, and the Quad Dipsea using it as start and finish line on November 29.
| Month | Event | What It Asks of the Park |
|---|---|---|
| June | Dipsea Race | Downtown plaza start, Old Mill Park race route |
| August | Double Dipsea | Turn-around point and aid station |
| September | Escape from Alcatraz Triathlon (Dipsea portion) | Race start |
| September | Fall Arts Festival | Full park closure, roughly a week of setup and breakdown |
| October | Zero Breast Cancer Hike/Run | Start and finish |
| November | Quad Dipsea | Start, finish, and mile 14 drop-bag turnaround |
That is six separate uses of the same small footprint of land, spread across six months of the year, all converging on the intersection where Throckmorton Avenue meets Cascade Way and Old Mill Street. Anyone who has wondered why that corner seems to close down for setup crews or fill with runners on a random Saturday now has the explanation. The park is not overbooked by accident. It is the only place in Mill Valley where a downtown plaza, a creekside grove, and the base of the Dipsea stairs all meet in one spot, which makes it the natural staging ground for nearly everything the town hosts outdoors.
Two Weeks From Now, the Double Dipsea Already Sold Out
The nearest event on that list has already closed its doors to new entrants. The 56th annual Walt Stack DSE Double Dipsea runs on August 22, 2026, a 13.7 mile out and back that starts at Stinson Beach, climbs the Dipsea Trail into Mill Valley, and turns around to retrace the same route back to the coast. Registration for 2026 has reached capacity and is closed, which means every runner on the trail that Saturday already has a bib.
The race uses a handicapped start, a format in which slower runners set off first and the fastest wave leaves last, so that finishers arrive close together regardless of pace. Everyone gets a head start except the fastest men's division. The result on the ground is a compressed window, roughly midmorning into early afternoon, when the stair base and the lower trail near Mill Valley see a wave of runners moving through in both directions. Organizers ask participants to skip headphones and trekking poles on course for safety, a rule that has been in place since 2015 given how narrow the single-track sections are near the Mill Valley end.
For a resident walking the dog near the trailhead that Saturday, the practical note is simple: expect company on the lower Dipsea steps from late morning through early afternoon, and expect the small aid station and turn-around presence near the park to occupy space that is normally open.
The Festival Turns 69
About four weeks later, the same ground hosts a very different kind of crowd. The Mill Valley Fall Arts Festival returns to Old Mill Park on September 19 and 20, 2026, marking its 69th year. The festival dates back to 1957, when a small group of artists first exhibited work in downtown store windows, and it became a nonprofit in 1962 when it found its permanent home at Old Mill Park, a setting it has kept for more than six decades.
This year's event brings roughly 135 juried artists working in painting, sculpture, ceramics, jewelry, textiles, glass, and photography, spread beneath the redwoods across two full days from 10 a.m. to 5 p.m. This year's poster, titled Golden Beams, was selected from work by local artist Hilary Williams. The music lineup draws from the Bay Area's own roots scene, including a bluegrass set from Mill Valley's own Spencer Krenz and songs from Marin singer-songwriter Meggy Travers, spanning bluegrass, folk, Americana, and jazz across the weekend.
"Our music stage brings together some of the Bay Area's favorite performers in one of the most beautiful outdoor venues imaginable," said MVFAF President Liz Lauter. "It's the perfect soundtrack for a weekend celebrating art, creativity, and community."
Kids get their own corner of the park in the Children's Grove, where a character called the Blue Fairy hosts puppet shows and storytelling, MarinMOCA runs hands-on art tents, and Woander leads woodland storytelling built around characters from Wylding Woods. Parking downtown fills quickly during the festival, so the event runs a free shuttle from the Edna Maguire and Mill Valley Middle School lots with continuous service both days. Based on the city's typical permitting pattern, the park itself is generally reserved for close to a week around the event, from setup through breakdown, which is worth knowing if a regular walk or a weekday errand usually routes through that corner of downtown.
The Stairs Locals Walk Past Are on a Repair List
The Dipsea Trail itself is not static. The stair section leading up from the Mill Valley trailhead was renovated in November 2017, bringing the total closer to 700 steps in that first mile, up from the 688 that longtime racers used to count. That renovation was not the last word. One Tam, the partnership that manages trail stewardship across Mount Tamalpais, Muir Woods, and the surrounding Marin Water lands, has identified drainage and erosion problems on the intertwined Dipsea Trail and Deer Park Fire Road, and has a plan to replace a set of decaying wooden stairs with Civilian Conservation Corps style stone ones once funding is secured.
The work is not yet scheduled. It sits on a list, tied to funding that has not arrived, alongside a related commitment to step up weed management in the area to protect the Oakland star tulip and other native plants that grow along that stretch. A separate but nearby project, the Redwood Creek Trail Realignment and Floodplain Restoration, has already relocated 1.1 miles of trail near Muir Woods to improve passage and protect the creek, with a floodplain restoration phase still to come. Taken together, these are signs of a trail system under active, ongoing management rather than one that simply gets walked on and left alone. For anyone who uses the lower Dipsea Trail regularly, that decaying stair section is a known, tracked problem, not a surprise waiting to happen.
Thanksgiving Weekend Closes the Loop
The fall stretch closes with the most demanding event of the year. The Quad Dipsea runs on Saturday, November 28, 2026, the Saturday after Thanksgiving, and it starts and finishes exactly where the season began, at the intersection of Throckmorton Avenue, Cascade Way, and Old Mill Street. The race covers 28.4 miles, two out and back trips along the full Dipsea Trail with no shortcuts permitted, and roughly 9,200 feet of climbing matched by an equal amount of descent. Runners can leave a drop bag at the Old Mill Park turnaround, mile 14 of the course. First held in 1983 with only eight runners, the race is now capped at around 250 participants, a small but committed field that makes the same demanding climb four times in a single day.
By the time the Quad Dipsea wraps up, Old Mill Park has done its full year of work: a June race, an August aid station, a September triathlon start layered under a September arts festival, an October hike and run, and a November ultramarathon that both opens and closes on the same six blocks. None of it is hidden. It is all on the city's own public calendar, year after year, in roughly the same slots. It just rarely gets read as one continuous story until someone lines up the dates.
For residents, the practical value of seeing it this way is simple. The park's rhythm predicts the town's traffic, parking, and foot-crossing patterns more reliably than any single event announcement does. Knowing the shape of the whole season, rather than reacting to each closure as it comes, is what makes it possible to keep walking that same familiar loop through the redwoods without missing a beat.
If you are thinking about what it actually feels like to live near this corner of town, day to day and season to season, that is exactly the kind of local detail worth talking through. Julia Camajani has spent years getting to know Mill Valley at this level of detail. Let's Connect.
