Great Falls Half (Half/10k/5k)
Great Falls Half (Half/10k/5k) logo

Great Falls Half (Half/10k/5k)

Potomac, Maryland, United States
Nov 21, 2026 (America/New_York local time)
Running

About this race

Great Falls Half, 10K & 5K
Saturday, November 21, 2026 · Great Falls Tavern, Potomac, MD

Run the C&O Canal towpath along the Potomac, starting and finishing beside Lock 20 at Great Falls Tavern. All three distances head south along the canal past Widewater, Old Angler's Inn and Carderock, then turn for home. The towpath is flat, shaded crushed stone that was built for mules and is perfect for a fast fall race. Late November is the towpath's best season: the crowds are gone, the air is cool, and with the leaves down you get long views of the river.

Every runner is tracked live on Geo.Racing, so your people can follow you down the towpath and be at the line when you finish. Collect your medal, then walk the boardwalk to the Great Falls Overlook and watch the Potomac pour into Mather Gorge.

Start times: Half marathon at 12:00 PM, 10K at 12:30 PM, 5K at 1:00 PM. Finish line closes at 3:00 PM.

Every entry includes: a race shirt, a finisher medal, chip timing and results, aid stations on the towpath, and live GPS tracking. Awards go to the top three men and women at each distance.

Good to know: the field is capped under our National Park Service permit, so register early. The park charges $20 per vehicle (card only) at the Great Falls Tavern gate, and parking is limited, so carpool if you can. The towpath stays open to other walkers and cyclists: keep right and pass on the left.

Presented by Old Dominion Racing.

Pick your distance

Running

Great Falls Half Marathon

Nov 21, 2026 Half-Marathon 12:00 PM
$85.00
Open

Great Falls 10k

Nov 21, 2026 10K 12:30 PM
$75.00
Open

Great Falls 5k

Nov 21, 2026 5K 1:00 PM
$65.00
Open

Typical race-day weather

Based on 1 year of Open-Meteo archive data for this event's race dates in Potomac, plus the 3 days either side.

Temp (°C)
Minimum temperature (race-week average) 1.7° / Maximum temperature (race-week average) 9.5°
Feels Like (°C)
Minimum feels like — heat index / wind chill (race-week average) -2.1° / Maximum feels like — heat index / wind chill (race-week average) 7.4°
Peak wind (km/h)
Strongest wind of the day (race-week average)
13.9
Precip (mm)
Precipitation over the day (race-week average)
4.7mm
Humidity
Mean relative humidity (race-week average)
73.0%
Sunrise
Sunrise at the start line on November 21, 2026 (EST)
Sunset
Sunset at the start line on November 21, 2026 (EST)
Daylight
Hours between sunrise and sunset on race day
9h 52m

The sun rises at 6:58 AM and sets at 4:50 PM local time (EST) in Potomac on November 21, 2026 — 9h 52m of daylight.

Course

No course map published yet.

The organizer hasn't released a route for this event, and we don't publish guesses. If you're the organizer, send us a GPX file and we'll draw the profile.

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Where this page comes from. Race details were last updated on . We re-check listings regularly and again in the week before race day.

  • Entries, prices, waves and inclusions — the event's official registration page
  • Temperature and humidity — Copernicus ERA5 reanalysis via Open-Meteo (CC BY 4.0)
  • Elevation and terrain relief — Copernicus DEM GLO-90, ESA (CC BY 4.0)
  • Comparisons and counts — Race Discovery calendar, 10 Potomac events

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