In 42 days · Sun, Dec 13, 2026
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Sunday, December 13th, 2026
North Parking for Carderock Cliffs, Potomac MD
Half
31–45°F · some rain risk
See last 10 years
On this date: rain 1 of the last 10 years
2025
26–42°F
dry
2024
25–38°F
dry
2023
33–46°F
dry
2022
26–40°F
dry
2021
28–51°F
dry
2020
43–59°F
dry
2019
31–44°F
rain
2018
33–47°F
dry
2017
21–32°F
dry
2016
33–45°F
dry
Best months to race in Maryland →
About this race
The lowest-priced half-marathon in America! Still a full 13.1 miles and full-service on quality and support!
This is race #2 of the DCRR Snowball Series. In past years, it's been the Gar Williams Half Marathon; now it honors all the Club's founders.
Course : Out-and-back along C&O Canal Towpath. Previously-USATF certified course, click here for map. We intend to recertify the course before race day, subject to completion of construction in the vicinity of Canal Lock 5. We'll make sure the course is accurately measured to account for the slightly-different path through the construction site if they're still digging.
Water Stops : There will be two water stops: one at Lock 10 and one at Lock 6. These locations correspond to approximately mile 3, 5, 8, and 10 of the race. You will run by each water stop twice.
Registration : Online registration only.
Timing and Results : Timing and results will be compiled on a real-time basis and friends and family will be able to track runners throughout the race via social media.
We will provide a link for live results in our final instructions to runners..
Fees : Online advance registration through 24 hours before the race (9:00 AM on 12/12). After that, late registration will be open until the moment the race begins, at a slightly higher price.
¶ Advance registration: $0 for DCRRC members, $10 for non-members.
¶ Late registration: $5 for DCRRC members, $15 for non-members.
Refund policy for Snowball Series : In the event the race is canceled, pre-paid non-members will receive a credit to be applied to a future Snowball Series race.
Location : Carderock Recreation Area (not Park), Carderock, MD.
Raceday Timeline :
7:30 Packet Pickup opens
9:00 Race Start
11:00 Awards
12:00 Course Closes
Amenities and extras : We will have a great breakfast spread post race, including bagels, cream cheese, Nutella, PB&J, hot chocolate, coffee, tea, Gatorade, bananas, and more.
T-shirts and Medals : Come on people, it's a $10 race... No, there are no t-shirts or medals.
Directions : Take the Capital Beltway (I-495), to the Clara Barton Parkway headed west, outside the beltway. Make a right on the first exit which is for both Carderock and the Naval Surface Warfare Center (Carderock Division). Turn left at the stop sign at the top of the ramp to cross the parkway. After passing under the canal, turn right and proceed to the last parking lot. If it's full, park in one of the other lots and walk back to our registration area.
Volunteers : We need many volunteers to help coordinate the race events. Please "pay it forward" by helping if you're not running, or have a friend or relative volunteer. Remember, this counts as your Snowball Series volunteer requirement.
Course map
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