Petaluma River Marathon and Half Marathon

  • Hosted By North Bay Rowing Club


The Petaluma River Marathon is one of the most beautiful and fun races on the west coast.  The water is usually flat at race time, and there is little interference from motorboat wakes. The air temperature is cool at start time. The event is timed on the “river” (actually an  estuary) so its direction of flow will favor racers. 
For most of its course, the river flows through a nature preserve that conveys an impression of pre-Conquest California. In the foreground, the competitors will pass next to native plants and wildlife, and in the background the California coastal range rises to define the horizon.
Fortunate coincidence: The river is almost precisely 13.1 miles from the end of its navigable channel in downtown Petaluma to its mouth at San Pablo Bay. Accordingly, our course, from the NBRC dock to the Highway 37 bridge and back, covers approximately the standard marathon distance. Half Marathon participants will turn at a buoy at the halfway point.
There will be a brief participants meeting at 7:00 am. Marathon boats will start at 7:30am, and Half Marathon boats immediately afterwards.  The race begins and ends at the North Bay Rowing Club at the south end of 2nd Street in Petaluma California. Enter 38.2314° N, 122.6294° W in the search box on Google Maps to see the start and finish point. Racers can park in the parking lot at Foundry Wharf adjacent to the gate into the North Bay Rowing Club boatyard.
The full marathon (26.2 miles) will begin at the NBRC dock in Petaluma, go downriver 13.1 miles, turn around under the Highway 37 bridge near the mouth of the river, and return to the start. Enter 38.115° N, 122.505° W in the Google maps search window to see the downstream turn for the marathon. Boat should enter third arch from Marin side and return on the fourth..
The half marathon will begin at the same point and turn around at a buoy marking the halfway point (38.1831° N, 122.5437° W).
Traffic Pattern: Participants MUST KEEP STARBOARD NEAR SHORE AT ALL TIMES (especially including turns to port). Be prepared to give way to any tug/barge should one appear.

Tides: In celebration of two of Petaluma’s key economic attributes, ecotourism and artisan food, the moon is lined up to assure ample time to inculcate the wondrous beauty of our tidal wetlands during the opening half of your voyage, then carry you home easily to the shared feast in time to be enjoyed at leisure.   Surely, an experience to be envied by Cittaslow!


For those unsure of reading between the lines, we’ll start toward San Pablo Bay as the tide begins to flood, then ride it home.  The tide will rise as much as five feet, making it easier to carry your boat up from the dock after you finish (you’re welcome).  The particulars:



Low Tide

High Tide











Half Marathon Turnaround





Full Marathon Turnaround