Curated races, clubs, and training

MarathonThe full 26.2 Half Marathon13.1 miles of fun 5KShort and fast 10KThe classic distance TrailGet off the pavement RoadPavement classics Ultra50K, 100K, and beyond FlatFast, PR-friendly courses DownhillNet elevation drop RelayRun as a team VirtualRun anywhere, anytime CoastalRun along the shoreline MountainHigh-altitude challenges

5KShort and fast 10KThe classic distance Half Marathon13.1 miles of fun MarathonThe full 26.2 50KYour first ultra 50 MileThe long haul 100KUltimate endurance 100 MileThe ultimate challenge

All trail racesGet off the pavement Mountain TrailsAlpine singletrack Coastal TrailsOcean views on foot Hilly TrailsRolling terrain off-road Flat TrailsSmooth and fast off-road Trail Ultras50K+ off-road Trail 50KFirst ultra on dirt Trail Marathon26.2 off-road Trail Half13.1 off-road

All road racesPavement classics Road MarathonClassic 26.2 on pavement Road Half13.1 on the roads Road 10K6.2 miles on pavement Road 5KFast 3.1 on the roads Flat RoadPR-friendly road courses Downhill RoadNet downhill road courses City RoadUrban road events

United StatesRaces across America Boston, MAHistoric running city New York, NYThe five boroughs Chicago, ILFlat and fast Los Angeles, CAWest coast running San Francisco, CAHills and views Denver, COMile high racing Portland, ORPacific Northwest Seattle, WAEmerald city runs Austin, TXTexas running scene Nashville, TNMusic city miles San Diego, CAYear-round sunshine Miami, FLTropical running Honolulu, HIIsland paradise runs Washington, DCMonument runs Salt Lake City, UTMountain valley racing Boulder, CORunner's paradise Bend, ORTrail town USA Asheville, NCBlue Ridge running Duluth, MNNorth Shore trails Charleston, SCSouthern charm runs Savannah, GALive oak lined routes Santa Fe, NMHigh desert art town Key West, FLSouthernmost runs Maui, HIVolcanic island trails Napa Valley, CAWine country running

FlatFast, PR-friendly courses RollingGentle hills throughout HillySignificant climbs MountainousMajor elevation challenges DownhillNet elevation drop CoastalRun along the shoreline MountainHigh-altitude challenges ValleyBetween the peaks IslandSurrounded by water CanyonDeep and dramatic DesertArid and exposed

OceanRun along the ocean LakePeaceful lake views RiverFollow the water BayHarbor and bay views WildernessDeep backcountry RuralQuiet country roads CityUrban energy LoopStart and finish together Point to PointA to B adventures Out & BackThere and back again

Turkey TrotThanksgiving weekend runs New Year'sStart the year running July 4thIndependence Day runs Valentine'sRun with your sweetheart St. Patrick'sLucky runs in green HalloweenSpooky season runs Memorial DayHonor and run ChristmasHoliday season runs Labor DayEnd-of-summer runs Mother's DayRun for mom Father's DayRun for dad Cinco de MayoFiesta runs MLK DayDream runs

YosemiteSierra Nevada running Grand CanyonRim-to-rim adventures ZionRed canyon trails YellowstoneGeothermal wilderness Big SurCoastal California SedonaRed rock running MoabDesert ultra country Lake TahoeAlpine lake running AcadiaNortheast coastal trails GlacierCrown of the continent Death ValleyExtreme desert running Joshua TreeHigh desert trails Rocky MountainAlpine trail running OlympicRainforest to coast Bryce CanyonHoodoo trails Great Smoky MountainsAppalachian running LeadvilleRace across the sky Mount RainierVolcanic peak trails Pictured RocksGreat Lakes shoreline

RelayRun as a team VirtualRun anywhere, anytime WalkingWalk-friendly events TrackOn the oval GrassSoft underfoot SandBeach running MixedVariety of terrain LapsMultiple loops

About Pricing Brand Terms Privacy

© 2026 Intervals

Races Clubs Train Wrapped

4K Trail Run — Boston, MA

Races
United States
Massachusetts
Boston, MA
4K Trail Run

Trail Island Ocean City

4K Trail Run

Wednesday, May 20, 2026Boston, MA4K

Experience a truly unique race on Cathleen Stone Island, located right in the heart of the Boston Harbor. This 4K trail run offers a scenic escape from the city, beginning with a relaxing 30-minute ferry ride to the island. Participants can choose to run on either May 20th or May 21st, 2026, making it a flexible option for teams and individual runners alike. Beyond the race, the event features a post-run celebration complete with dinner, beer, and an on-island party. Most importantly, every registration supports the island's mission to provide free, hands-on science education to Boston's youth...

Race

Surface

Trail

Temperature

Mild

Setting

Island

Waterfront

Ocean

Area

City

May 204:00 PM

Shirt

Closed

FAQ

Location

May 204:00 PM

Shirt

Closed

Not affiliated with this event. Official website. We may earn a commission on registrations.

Cathleen Stone Island

Boston, MA 02210

More races near Boston

Wayniacs Weekly Robinson Run

Madbury Day Fun Run

Mine Falls Summer Trail Series

3.1 Miles5 Miles5K

TVFR Woodland Trail Series

TVFR Woodland Trail Series - All 3 racesTVFR Woodland Trail Series - June & JulyTVFR Woodland Trail Series - June & August+4

Cirque Series - Cannon Mountain, NH

6.9 MilesVolunteer

Guinness Celtic 5K (Race 2 Greendale Physical Therapy Worcester Triple Crown)

Dublin School Outdoor Center Trail Race

Stone Tower Half Marathon

Anchor Down Ultra

Preferred Entry: 6-HourPreferred Entry: 12-HourPreferred Entry: 24-Hour+3

Breast Cancer Awareness 5K Run/Walk

Paul Funk's Dolphin Dash

South Yarmouth, MA