Overview
The Clarence DeMar Marathon draws approximately 308 finishers each September on a scenic road in Keene, United States. The Clarence DeMar Marathon honors a six-time Boston champion on a USATF-certified course through the Monadnock Region. The course passes Surry Mountain Dam, Bretwood Golf Course, and historic Keene neighborhoods during peak foliage season. Rolling terrain with moderate climbs shapes the middle miles.
Clarence DeMar Marathon is a certified 42.195 km (26.2 mile) marathon — the standard World Athletics marathon distance.
Clarence DeMar Marathon 2026 race day
The next Clarence DeMar Marathon is scheduled for Sunday, 6 September 2026 with a 7:00 am start. The certified course covers 42.195 km (26.2 miles) with 150 m of climbing on a rolling with moderate climbs layout.
Clarence DeMar Marathon course route
The Clarence DeMar Marathon is a rolling scenic road course with moderate climbs. Starts in Gilsum and finishes on Appian Way at Keene State College. The course passes Surry Mountain Dam, Bretwood Golf Course, and historic Keene neighborhoods during peak foliage season. Rolling terrain with moderate climbs.
Clarence DeMar Marathon elevation profile
The Clarence DeMar Marathon course is rolling with moderate climbs over 42.195 km (26.2 miles). Runners cover 150 metres of climbing and 140 metres of descent, with a net climb of 10 metres from start to finish.
Entry requirements
Clarence DeMar Marathon is typically held in September. Registration opens through https://clarencedemar.com/ and may use a lottery or tiered entry when demand exceeds capacity.
Frequently Asked Questions
- What is the Clarence DeMar Marathon elevation profile?
- The Clarence DeMar Marathon has 150 metres of total climbing and 140 metres of descent over 42.195 km (26.2 miles). The course is rolling with moderate climbs, with 10 metres of net climb from start to finish.
- How long is the Clarence DeMar Marathon?
- The Clarence DeMar Marathon is the standard marathon distance of 42.195 kilometres (26.2 miles), certified to World Athletics rules. The Clarence DeMar Marathon is a scenic road through Keene.
- What time does the Clarence DeMar Marathon start?
- The 2026 Clarence DeMar Marathon starts at 7:00 am local time on Sunday, 6 September 2026. Arrive early for baggage drop and corral access — official race communications on clarencedemar.com/ confirm any last-minute schedule changes.
- Where does the Clarence DeMar Marathon start and finish?
- Starts in Gilsum and finishes on Appian Way at Keene State College. Updated course maps are published at https://clarencedemar.com/ each year.
- When is the Clarence DeMar Marathon and how do I register?
- Clarence DeMar Marathon is typically held in September. Registration opens through https://clarencedemar.com/ and may use a lottery or tiered entry when demand exceeds capacity.
- Is the Clarence DeMar Marathon course flat?
- The course includes rolling with moderate climbs. Study the official course profile at https://clarencedemar.com/ before setting pace targets.
- What landmarks does the Clarence DeMar Marathon pass?
- The route runs from Gilsum through Surry Mountain Dam into historic Keene and Keene State College.
- What weather should runners expect at Clarence DeMar Marathon?
- Cool September mornings with early New England foliage and comfortable racing temperatures.
Last updated 18 July 2026. Edition dates and course details are reviewed regularly.
