Walnut Avenue closes to traffic on Saturday, Oct. 24, from 4 to 8 p.m. for the fourth annual Mare Island Halloween Block Party. The Officers Row mansions get decorated, and the entrances sit near the Vino Godfather Mansion and Alden Park. Admission is free, but you need to RSVP through the event's Eventbrite page. Kids 13 and under who trick-or-treat get a goodie bag while supplies last.
Getting there is the same short drive across the Mare Island Causeway. Getting home at 8 p.m. means going north and crossing the Napa River on Highway 37, because the causeway's single open lane only carries traffic onto the island. That same weekend, a 55-hour full closure of State Route 37 between Vallejo and Sonoma is scheduled. For this year's party, the trip home matters as much as the party itself.
The causeway has carried traffic one way for a year
The City of Vallejo's project page says that since Oct. 7, 2025, the bridge's one open lane has been "used for westbound traffic at all times." Everyone leaving the island for the mainland has to use Highway 37. The City expects that pattern to last through March 31, 2027, when it plans to finish the bridge's preventive maintenance. That work covers concrete spall and crack repairs, fender system repairs for boat traffic, and new underwater anodes.
Treat that end date as a target. In July, the Vallejo Sun reported that the lift span had gone back to normal operation on July 1, while other work had been delayed by California black rail nesting. At that point the City still estimated the repairs would be done in March 2027. On Oct. 13, the City announced a full closure for Saturday, Oct. 17, from 9 a.m. to 3:45 p.m., covering cars, bikes, pedestrians and boats. The east side of the span had developed a mechanical imbalance that threw it out of vertical alignment, and the City described the fix as urgent corrective maintenance. Four days' notice for a full closure shows how quickly access to the island can change.
The City's Oct. 13 release is the latest word on who can cross and when:
| Getting across | Weekdays through Oct. 23 | Saturday, Oct. 24 |
|---|---|---|
| Car onto Mare Island | Causeway, single westbound lane | Causeway, single westbound lane |
| Car back to the mainland | Highway 37 via the Napa River Bridge | Highway 37, during a scheduled 55-hour SR 37 closure between Vallejo and Sonoma |
| On foot or by bike | Causeway and trails beneath it closed | Causeway open |
| Foot and bike alternatives | SF Bay Ferry between Mare Island and the Vallejo terminal, or a Highway 37 detour of about 2.6 miles | Same, if you'd rather skip the causeway |
The party weekend also lands on a Caltrans job. On Oct. 14, Mare Island Co. posted notice of a 55-hour full closure of State Route 37 between Vallejo and Sonoma, scheduled from Friday, Oct. 23 at 10 p.m. to Monday, Oct. 26 at 5 a.m. Before you count on Highway 37 to get home Saturday night, check Caltrans' posted limits and detours for that closure.
On Saturday, walkers and bikes can cross both ways
The one-way rule only applies to cars. For people walking or riding a bike, the restriction is a weekday closure. Through Oct. 23, crews are applying polyester concrete and methacrylate to the deck from 7 a.m. to 5 p.m., Monday through Friday. The City says those materials contain chemicals classified as carcinogenic and can give off strong odors, so the bridge and the trails under it stay closed to pedestrians and cyclists while the work goes on. The crossing reopens each Friday at about 5:15 p.m. and stays open Saturday and Sunday. The City also asks open-deck boats to stay out from under the bridge during weekday work hours.
That makes a mainland household's options for the block party lopsided. A family that drives can get onto the island directly, but on the way out at 8 p.m. they'll be headed for Highway 37 with everyone else leaving Walnut Avenue, during the weekend Caltrans has that route scheduled for a full closure between Vallejo and Sonoma. A family that walks or bikes from the downtown side can use the causeway in both directions on Saturday, since the release lists every Saturday except Oct. 17 as open. Anyone who needs help with accessibility can reach Public Works at (707) 648-5235 or [email protected], according to the City.
The island has one fewer place to eat and drink
The detour matters more this October because the island has fewer places to stop. The Redwood Empire Bar and Eatery at 1095 Nimitz Ave. closed on Oct. 4. The Vallejo Sun reported that the whiskey distillery, which moved to Mare Island in 2025 when it bought Savage & Cooke's site, made the call to focus on its core business. Andrew Floor, the company's vice president of marketing, told the paper:
"We are in the business of making California's best whiskey, and a whiskey that can challenge other whiskies across the country. We are not restaurateurs."
The distillery is still running in its historic buildings. It's open for tours, tastings, classes and events by reservation only. The 90-minute tour covers the barrel room, the production room and the rooftop balcony, and it ends with a guided tasting of six whiskies. Floor told the Vallejo Sun that the company hopes to reopen for daily drop-in visits once Mare Island gets more foot traffic.
That leaves two places for an unplanned stop near the party:
- The Coal Shed, Mare Island Brewing Co.'s brewery at 850 Nimitz Ave., serves food and drinks with indoor and outdoor seating. Its own page lists Wednesday through Saturday hours of 11:30 a.m. to 9 p.m. and Sunday hours of 11:30 a.m. to 8:30 p.m.
- The Quarters Coffee House on Officers Row along Walnut Avenue is open 8 a.m. to 2 p.m. on weekends and sells coffee, tea, snacks and locally made goods.
At the party itself, there will be food trucks, hot chocolate, beer and wine, according to the organizers and the Vallejo Times-Herald.
Planning Saturday around the 8 p.m. exit
Here's what the program includes. Returning favorites include a pumpkin patch, pumpkin painting, trick-or-treating and dancing, according to the Vallejo Times-Herald's Oct. 13 preview. The event listing adds face painting and a "Howl-o-ween" costume contest for dogs. New this year, Alden Park has been taken over by zombies, which the listing pitches as a photo spot. Rebecca Kotch, Mare Island Co.'s vice president of marketing, told the Times-Herald that "the mansions would be the perfect venue to close the road, decorate the mansions, and have an afternoon Halloween gathering."
With the causeway set up the way it is, a workable Saturday looks like this:
- RSVP first. Admission is free, but the organizers require an RSVP through Eventbrite.
- Pick the entrance before you park. The two entrances are near the Vino Godfather Mansion and near Alden Park, where the zombie setup is.
- Decide how you'll leave before 4 p.m. If you drive, your way home is Highway 37, so check the Caltrans detours for the Oct. 23 to Oct. 26 SR 37 closure before you go. If you walk or bike from the mainland, you can come back over the causeway, since Saturday is an open day.
- Leave room after 8 p.m. The Coal Shed is open until 9 p.m. on Saturdays, an hour after the party ends, so you can have dinner on the island instead of joining the line of cars leaving Walnut Avenue.
The rest of Halloween week stays on the mainland
The Greater Vallejo Recreation District runs Nightmare on Glenn Street at Children's Wonderland Park on Friday, Oct. 30, from 5 to 8 p.m. It's free and includes a haunted house, a trick-or-treat lane and a costume contest. On Saturday, Oct. 31, Vallejo Main Street's Downtown Costume Contest & Stroll runs from 10 a.m. to 2 p.m. during the farmers market. It includes trick-or-treating at downtown businesses, a haunted house, and a costume contest at Bambino's, judged at 1 p.m.
What changes on Mare Island in November
Two changes on the island's calendar come in November. The Mare Island Historic Park Foundation runs reservation-only tours at St. Peter's Chapel, 1181 Walnut Ave., during the first and third weeks of each month. Tours run Saturdays at 10 a.m. and 2 p.m. and Sundays at 2 p.m. The chapel-only tour costs $15, and the full historic tour costs $25. The block party falls on the fourth Saturday, so the next tour weekend is in November. Redwood Empire also has a blending masterclass with master blender Lauren Patz scheduled for November.
The ferry schedule changes too. Starting Monday, Nov. 2, San Francisco Bay Ferry is dropping the 11:30 a.m. northbound weekday trip on the Vallejo route. The 11:05 a.m. and 12:10 p.m. departures stay, and southbound service doesn't change. Under the fare program that started July 1, the Vallejo regular fare is $10 and the discounted fare is $5. The City lists the ferry between Mare Island and the Vallejo terminal as a way across for people on foot or bikes, so check the Vallejo route schedule before you count on it.
The causeway is expected to stay one-way through March 31, 2027. Until then, every evening on Mare Island ends with the drive out over the Napa River Bridge.
If you own a home on Mare Island and want to know how a one-way causeway, a closed bar and the island's other changes this year might factor into your timing, Kevin Johnson can walk you through what buyers are weighing right now. Get a Free Home Valuation and start with real numbers on your own property.
