The U.S. Army Corps of Engineers closes the one-lane Cabin John Bridge, also called the Union Arch Bridge, from 7 a.m. to 3 p.m. on Saturday, Nov. 7. It is the middle link of MacArthur Boulevard. The timing is apt. For the next eight weeks, the two ends of MacArthur run opposite calendars. Great Falls, at the western end, is being shut down for winter. Glen Echo Park, at the eastern end, opens a holiday season on Nov. 14 that runs until Jan. 10.
For anyone in Potomac who treats MacArthur as the weekend road, that changes the plan. From now through December, the busy end of the boulevard is the eastern one, and every stop along the way has a date worth knowing.
On Nov. 7, the Middle of the Road Closes
According to Montgomery County's notice, the closure covers the Corps' annual inspection of the bridge and minor repairs. Inspectors check for concrete cracking, steel corrosion, section loss, and movement at bearings and joints. The bridge is an 1864 stone-masonry arch, and it carries pedestrians and cyclists as well as cars.
- When: Saturday, Nov. 7, 7 a.m. to 3 p.m.
- Rain date: Sunday, Nov. 8
- Detour: Wilson Lane to River Road, and Seven Locks Road to River Road
- Questions: Washington Aqueduct maintenance, U.S. Army Corps of Engineers Baltimore District, 202-834-3731
The bridge reopens by mid-afternoon, so an evening on the Glen Echo end is unaffected. A Saturday morning spent driving the length of MacArthur is the trip to reroute.
The Great Falls End Is Being Put Away for Winter
At the western end, MacArthur Boulevard meets Falls Road at the Great Falls Tavern entrance. Here the change is a series of small shutdowns, each on its own schedule. The C&O Canal National Historical Park has already ended its Great Falls boat rides for the season. The canal is also draining. The park removes water from every watered section each fall to protect the stone masonry from freezing, a practice that dates back to the C&O Canal Company, and water usually comes back in early spring.
Locally, the draining has happened in stages. In the park's Oct. 14 water update, the pools from Lock 17 through Lock 21, the stretch past the Tavern and up toward Swains, still held water. The sections between Locks 21 and 23 were already dry, and so was most of the lower canal near Georgetown. The park publishes no date for draining the Great Falls pools, so for a few more weeks the canal near the Tavern may look different from one weekend to the next.
| What changes | When | What it means |
|---|---|---|
| Great Falls boat rides | Already closed for the season | No canal boat until spring |
| Faucets in camping areas | Typically around mid-November | Marsden Tract and the hiker-biker sites stay open, but campers bring their own water |
| Great Falls Tavern Visitor Center | Winter hours begin Dec. 1 | Open Thursday to Sunday, 9 a.m. to 4 p.m., closed Monday through Wednesday |
| Tavern holiday closures | Nov. 26, Dec. 24, Dec. 25 | Closed Thanksgiving, Christmas Eve and Christmas Day |
Wednesday is the day that disappears. The Tavern's standard schedule runs Wednesday through Sunday and closes only Monday and Tuesday. The winter schedule, from Dec. 1 through Feb. 28, closes Wednesday too. The restrooms are a separate matter. Park buildings and comfort stations draw municipal water, so the faucet shutoff at the campsites does not apply to the Tavern restrooms.
The trails, meanwhile, are open. As of the park's Oct. 27 conditions page, Billy Goat Trail Sections A, B and C, the Great Falls Overlook and Olmsted Island Boardwalk, the Gold Mine Loop and the River Trail were all listed as open. Section A is the one to check after a heavy rain. The park closes it when the Little Falls gauge reaches 5 feet and reopens it when the river drops to 4.8 feet.
Swains Lock Is Closed Because of a 2019 Storm
The Swains Lock parking lot at mile 16.7 closed Oct. 13. According to the National Park Service project page, the closure is expected to last "several weeks," and the page gives no reopening date.
The work goes back seven years. On July 8, 2019, a flash flood eroded the embankments along the Great Falls Entrance Road and damaged the timber retaining wall around the Swains lot. Crews are now rebuilding the embankments, placing dry-laid stone "rockery" walls, reconstructing road shoulders, installing a drainage pipe and stabilizing stream beds. At Swains, the timber wall is being replaced with an embankment of fill and seeded topsoil. The work is funded through the federal Emergency Relief for Federally Owned Roads program and is scheduled in phases through 2026, depending on weather.
Some practical details for the meantime:
- The Canal Quarters at Lockhouse 21 stays accessible during construction.
- The nearest towpath parking is Pennyfield Lock at mile 19.6, upstream, and Great Falls at mile 14.3, downstream.
- The Great Falls Entrance Road stays open, with occasional single-lane closures and delays possible.
This project does not fix the pavement on the entrance road. The park describes the current work as repairs to the substructure that keeps the road in place. A separate, larger pavement rehabilitation is still in design, with construction scheduled for some future date. The entrance serves more than 1 million visitors to Great Falls, Maryland, each year, so the rough surface will be around for a while.
The Glen Echo End Runs the Opposite Calendar
At the eastern end of the boulevard, Glen Echo Park's Light Up the Holidays season runs from Nov. 14, 2026, through Jan. 10, 2027. The Tavern starts its shorter winter week on Dec. 1. Glen Echo's busiest dates all fall in the weeks just before and after it.
- Saturday, Nov. 14. The Holiday Art Show & Sale opens from noon to 6 p.m. in the Popcorn Gallery, Stone Tower Gallery and Park View Gallery, followed by a reception from 6 to 8 p.m. At 6 p.m., Light Up the Carousel switches on the holiday lights on the 1921 Dentzel carousel, with hot apple cider. DIY holiday photos in the carousel run until 8 p.m. There are no carousel rides that night.
- Nov. 21 through Jan. 3. Adventure Theatre stages "Frosty The Snow Man."
- Nov. 27 through Dec. 31. The Puppet Co. presents its 38th annual "The Nutcracker."
- Saturday, Nov. 28. Shop Arts Saturday, timed to Small Business Saturday, opens the three galleries and the resident artists' studios for sales from noon to 6 p.m.
- Saturday, Dec. 5. Winter's Eve runs from 3 to 6 p.m., with children's holiday crafts, music, and open studios and galleries. Most activities are free, and the park asks for an RSVP but does not require one.
Glen Echo's three holiday Saturdays fall on Nov. 14, Nov. 28 and Dec. 5. The Tavern drops its Wednesday hours on Dec. 1, between the second and third of them.
What Stays Open in Between
The stretch of MacArthur between the two ends has its own winter schedule. Old Angler's Inn, at 10801 MacArthur Boulevard just east of the Great Falls turnoff, serves its dining room Wednesday through Sunday and closes Monday and Tuesday. Its Beer Garden hours depend on the weather. The inn's 2026 calendar lists Thanksgiving service on Nov. 26 from 11 a.m. to 8:30 p.m. and Christmas service on Dec. 25 from 11 a.m. to 9 p.m. Those are two of the days the Tavern visitor center is closed, so on Thanksgiving and Christmas the nearest open door at the Great Falls end is a restaurant.
At the Glen Echo end, The Irish Inn at Glen Echo has entertainment Sunday through Thursday. Its weekly events calendar lists Sunday jazz, Irish Inn Mates on Monday, trivia on Tuesday, a house band on Wednesday and music on Thursday. That makes it an easy stop before or after an evening at the park.
One familiar Cabin John stop is gone. Bethesda Magazine reported that the Bethesda Co-Op at MacArthur Plaza closed permanently on May 31, 2026. Proposals for the space included grocers, and Rodman's expressed interest, but no new tenant had been announced.
The boulevard itself is not changing this winter. Montgomery County's MacArthur Boulevard Bikeway Improvement Segment 3 covers 4.7 miles from I-495 to the District line. It would widen the sidepath on the south side to 8 feet with a 5-foot grass buffer, and widen the road from 20 to 26 feet where feasible. MCDOT's September 2026 update says the county expects Corps of Engineers approval by the end of this year and estimates that construction will begin in the third quarter of 2027. The stretch west of the Beltway, from Old Angler's Inn to Falls Road, is at an earlier stage. Its facility planning study has advanced to 5% design, with a public meeting held in January 2026.
If a winter along this stretch of MacArthur has you thinking about where in Potomac you might live next, or what your current home near the canal is worth, the team at Sison Homes and Associates knows these roads and the calendar that comes with them. Schedule a consultation, and we'll start with the part of Potomac you already know best.
