Manhattan Island Marathon Swim: My 7 Hour 35 Minute Journey
/On September 10, 2025, I completed my solo Manhattan Island Marathon Swim, circling the island’s entire 28.5-mile (45 km) perimeter in 7 hours and 35 minutes. After years of coaching and crewing this event, I finally took on the challenge myself. From the fast chop of the East River to the long, winding Harlem and the powerful Hudson, the day was a true test of rhythm, patience, and resilience—the essence of marathon swimming.
Coach Dan Daly swimming around Manhattan during the 28.5-mile Manhattan Island Marathon Swim
Urban Swim’s Swim Around Manhattan
Urban Swim’s Swim Around Manhattan—often called 20 Bridges—is one of the world’s iconic ultra-marathon swims. Sanctioned by the Marathon Swimming Federation, it follows traditional channel-swimming rules: no wetsuit - traditional swim suit, cap, goggles, no contact with the escort boat, and support limited to pilot vessels and kayakers who handle navigation and feeds.
Part of the Triple Crown of Open Water Swimming—alongside the English Channel and California’s Catalina Channel—Swim Around Manhattan typically draws about 100 experienced marathon swimmers each year between May and October.
The Course and the Tides
Manhattan is encircled by the Hudson, East, and Harlem Rivers, which together form a tidal estuary connected to New York Harbor and the Atlantic Ocean. Driven by the ocean’s semidiurnal tides, these rivers reverse flow roughly four times a day—two flood tides (flowing inland) and two ebb tides (flowing seaward).
Pilots and kayakers time the swim so athletes can ride the favorable currents, crossing beneath all 20 bridges (19 of which are on the east side!) that link the island to the mainland and outer boroughs while navigating shifting winds, standing waves, and converging river outflows. Most swims follow a counter-clockwise loop beginning at Pier A in the North Cove at Battery Park. Start times vary with the tide and swimmer’s projected pace; average solo times are 8–9 hours, while the most experienced athletes sometimes attempt the swim at night when tides are stronger, conditions calmer, and boat traffic lighter.
I was fortunate to train with and learn from two Guinness World Record holders Andy Donaldson and David Olvera, on their visits to NYC in preparation to set back-to-back 20 Bridges records in 2024 and 2025 with astonishing times of 5:41 and 5:39, respectively. Their guidance and inspiration were invaluable lessons to guide myself and other swimmers.
The Waterways
The Hudson, East, and Harlem are brackish, naturally silty rivers, so swimmers move through green-brown, often opaque water where visibility is just a few feet. Typical water temperatures range from the mid-60s °F (≈18 °C) in early spring to the mid-70s °F (≈24 °C) in late summer—comfortable but demanding for a multi-hour swim.
Once notorious for pollution, these waterways have undergone a remarkable recovery. Stricter environmental regulations and programs such as the Hudson River Estuary Program have boosted dissolved oxygen levels and reduced contaminants, allowing marine life—from striped bass and bluefish to seals and even the occasional dolphin—to rebound.
Organizations such as +Pool, Riverkeeper, and the Billion Oyster Project continue to improve access and water quality. Their work—building oyster reefs that naturally filter water, advocating for clean-water policies, and creating opportunities for New Yorkers to learn swimming skills—helps ensure that these rivers remain both ecologically vibrant and welcoming to swimmers.
Dan Daly completing Manhattan Island Marathon Swim – 28.5-mile open water marathon swim around New York City
Why This Swim Mattered
For me, the Manhattan Island Marathon Swim is far more than a line on a résumé. It blends every element of open-water swimming: endurance, navigation, tides, teamwork, and mental focus, all in the city I call home!
I had been “on again, off again” with this goal for years. Coaching others around Manhattan built my confidence, but it also reminded me how much respect these waters demand. The East River’s shifting currents, the Harlem’s steady grind, and the Hudson’s wide, unpredictable swells can break even the strongest swimmers without the right plan and crew. This year, everything finally aligned—training, support, and timing.
The Crew That Made It Possible
The Team That Supported Dan Daly’s Solo Swim Around Manhattan
No solo swim is ever truly solo. Here’s the team that turned this attempt into a success:
No marathon swim is truly solo. My success belonged to an extraordinary team:
Deanne and Gerry – Urban Swim: Their flawless planning and execution made the day seamless. Urban Swim events have long been where I built my comfort and confidence in New York waters.
My wife, Eszter: She crewed tirelessly and supported me through months of early mornings, long sets, and the fatigue of training.
Kevin, our boat captain, and his wife: Their navigation and communication through busy shipping lanes gave me complete trust so I could focus on my stroke.
Wendy, kayaker: Guided me through the fastest lines and kept me on course in turbulent chop.
Paul Frangipane: Captured the swim on camera—photos, drone shots, and a short documentary are coming soon.
Michael, official observer: A longtime Urban Swim volunteer who ensured every detail met Marathon Swimming Federation standards for ratification.
Ethan, companion swimmer: An age-grouper I coach, who joined part of the course, adding energy and gaining firsthand experience for his own future relay circumnavigation.
My dad and son: Cheering from the shore—a moment I’ll carry with me forever.
Friends, family, and the wider swim community: Everyone who came out to the course, followed along online, and sent good-luck wishes or congratulations—your encouragement meant more than I can say.
The Organizers: UrbanSwim
This swim wouldn’t have happened without the leadership and expertise of UrbanSwim. For years, they’ve been at the heart of open water swimming in New York City, offering safe, well-planned events that connect swimmers to the city’s waterways.
UrbanSwim doesn’t just organize races — they build a community. Their events introduce newcomers to open water in a safe environment, while also giving experienced swimmers the platform to take on marathon swimming challenges. I’ve had the privilege of coaching and swimming at many of their events, and it’s through those experiences that I gained the confidence needed to take on Manhattan myself.
Deanne and Gerry, the driving forces behind UrbanSwim, planned every detail of my swim with precision — from tides and timing to safety and support. Their commitment to swimmers and to New York’s waters made the day seamless.
What the Swim Felt Like
Seven and a half hours passed in distinct chapters—each stretch defined by currents, bridges, and landmarks.
The East River: Fast and technical, with chop and dense shipping lines that demanded constant attention.
The Harlem River: Long and steady, where the challenge shifted from muscles to mindset. We had chosen an aggressive pace that occasionally put me against the tide. I trusted both my pacing and the crew’s forecasts mile after mile.
The Hudson River: Wide, powerful, and humbling. The final miles tested every ounce of mental and physical strength I had left. Being in the middle of that large river reminds us how small we are, and that the real effort begins the moment we wish we were finished.
Dan Daly Powering Through the Waters of Manhattan Island
Fueling the Effort
In marathon swimming, it’s rarely the stroke that fails first—it’s the body running out of energy, or its ability to use energy efficiently for long periods. As I had practiced in my training, I paused every 30–40 minutes for a quick feed, usually just 15–20 seconds, taking 30 g of carbohydrate gel dissolved in 12 oz of water. I added a few 100 mg caffeinated gels later in the swim and used Liquid I.V. for extra sodium and a change of flavor (lemon-lime, my favorite).
Air and water temperatures that day were 71 °F / 21 °C, so I slightly reduced sodium intake. Cloud cover helped, and although we kept a few liters of hot water on the boat for warm feeds, I never felt cold. I maintained a steady 67 strokes per minute, holding pace and warmth throughout.
Essential Fueling and Hydration for Marathon Swimming Success
Training
My preparation balanced endurance, strength, and injury prevention.
Swim volume: In the spring I transitioned from a winter of sprinting (1–3 km sets, 3–12 km per week) to building 20–30 km weeks leading into Urban Swim’s Pride Swim in June, then on to the annual Lake Balaton 5 km. Training long-course outdoors in Budapest and logging open-water miles in Lake Balaton provided a range of conditions that mirrored New York’s variety.
Peak weeks: I reached 45 km for two weeks with two 4.5–5-hour swims, refining pacing, mental toughness, and fueling.
Strength & dryland: Year-round gym work, cycling through my 12 Week Athletic Development Plan, 2-3x week, transitioned to three weekly low-volume strength sessions early in the summer with kettlebells. As the event neared I shifted to two power-focused kettlebell workouts emphasizing speed of movement, then tapered by gradually reducing volume while maintaining intensity.
General marathon-swim guidelines recommend building weekly volume to at least match the event distance and completing a few long efforts—typically six-hour swims in water similar in temperature and conditions. My own preparation peaked at 45 km per week, including 4–5-hour continuous swims, and drew on my background in ultra-endurance events and races in the 5–10 km range. Although the Manhattan course is current-assisted, with an expected 7–9-hour finish, this training plan gave me the endurance and pacing practice I needed while keeping me strong, injury-free, and able to hold both speed and tempo for the entire swim.
Reflections
As I approached One World Trade Center, my team let me know I only had 30 minutes left to go. I felt gratitude more than relief—gratitude for my team, for my health, and for the chance to swim around one of the world’s greatest cities.
This wasn’t just a personal milestone; it was a reminder of why I coach. With the right preparation, mindset, and people, a daunting challenge can become a defining experience. For me, this achievement is part of a bigger journey.
What’s Next
Next week typically marks the close of my open-water season with the French Creek Racing Fall Swimfest 5K—a late-September race held in Hopewell Lake at French Creek State Park, surrounded by brilliant fall foliage and water temperatures in the low 60s °F. After a summer of training and racing in water 10–20 degrees warmer, this event always tests my tolerance for cooler conditions and is a fitting finale to the season.
After that, I’ll shift gears to shorter speed and power work in both the pool and the gym as I chase top 10 USMS national times in the 40–44 age group in the 50–100 m (SCM) and 50–100 yd (SCY) freestyle, breaststroke, and butterfly. I’m already posting in-season bests—close to lifetime marks—thanks to a smarter approach to technique, strategy, and training volume.
Ready to take on your own swim challenge? Join me at an upcoming Open Water Swim or USMS event, or set a goal of your own. For behind-the-scenes training notes, race prep, and open-water insights, follow me on Instagram for daily updates and coaching tips—and feel free to forward this newsletter to a swim-loving friend.
Author Bio:
Dan Daly is a swim coach with 20+ years of experience and founder of Train Daly. He specializes in helping swimmers break through performance plateaus, blending evidence-based training with practical application