Marathon du Lac de Der

France's largest artificial lake. 42.195 km of shoreline, forest trails, and open countryside. The Marathon du Lac du Der returns for its 13th edition on Sunday, June 14, 2026, starting in the historic center of Saint‑Dizier and finishing at the Giffaumont marina on the lake's edge. Choose solo, duo relay, or quartet relay. Maximum 2,500 participants — 1,000 solo, 250 duo teams, 250 quartet teams. Known for its festive, family‑friendly atmosphere and the infamous "best fancy dress" prize.

The Course:

• Start line: Avenue Belle Forêt sur Marne, Saint‑Dizier (facing Parc du Jard)
• Runners leave the city center and quickly reach the Lac du Der — the largest artificial lake in France, covering 48 km², created in the 1970s to regulate the Seine and Marne rivers
• The route follows the lake's shoreline, alternating between paved roads, quiet country lanes, and sections of forest trail
• Stunning views of the water, migrating bird flocks (the lake is a major European ornithological reserve), and the Champagne region's rolling landscapes
• Finish line at the Giffaumont nautical base — directly on the lake's edge, where spectators gather on the marina to cheer

Schedule:

• 7:00 AM — Collective warm‑up at Parc du Jard for all participants
• 7:30 AM — Mass start (all categories together)
• 2:00 PM — Finish cutoff. Runners still on course will be picked up by sweep vehicles.

What's Included:

• Chip timing (net time)
• Aid stations every 5 km with water, sports drinks, fruit, and snacks
• Medical support and first aid stations along the course
• Shuttle service between finish and start parking areas
• Finisher medal for every runner who completes the distance
• Post‑race refreshments (local specialties from the Champagne‑Ardenne region)
• Secure bag drop at start/finish
• Changing rooms and showers at Giffaumont base
• Free race photos available for download after the event

Logistics:

• Bib pickup: Saturday, June 13 (location TBD) and race morning from 6:00 AM at Parc du Jard, Saint‑Dizier
• Parking available at Saint‑Dizier city center lots and at Giffaumont base (shuttles run between both)
• Shuttle buses transport relay runners to their exchange points
• Baggage transfer: bags left at Saint‑Dizier start are transported to Giffaumont finish

The Fancy Dress Tradition:

• The Marathon du Lac du Der is famous for its "best costume" prize
• Runners and relay teams frequently complete the entire 42 km in elaborate outfits — superheroes, animals, historical figures, food items, you name it
• Awards ceremony at the finish line celebrates both the fastest runners and the most creative costumes
• Past editions have seen full medieval armor, banana costumes, and a four‑runner centipede outfit

Charity & Community:

• Organized by Association CAP DER, a local volunteer‑run organization
• Proceeds support youth sports programs and the preservation of the Lac du Der nature reserve
• The event brings together 2,500 runners + 500 volunteers + thousands of spectators lining the course

Partners include local and national brands (complete list on event website).