ATW Centurion 100KM Triathlon Box End

The ATW Centurion 100KM Triathlon is a specialized endurance event held at the Box End Park in Bedford, United Kingdom. Scheduled for Sunday, May 24, 2026, the race follows the increasingly popular 100km "Metric Centurion" format, often utilized in professional race series. The event is organized by Active Training World (ATW), one of the UK’s largest multisport organizers, and serves as a significant bridge for athletes moving from standard distance triathlons to half-Ironman challenges.

Event Logistics and Participant Information:

• -- Alternative Categories: For those not wishing to complete the full triathlon, an Aquabike (swim-bike only) option and a Relay option (teams of 2 or 3) are available. Sprint and Standard distance triathlons are also hosted at the venue on the same day.
• -- Strict Time Cut-offs: The swim has a 2-hour 30-minute cut-off, the bike must be completed within 6 hours 30 minutes of the start, and the total race must be finished within 8 hours 30 minutes.
• -- Venue Amenities: Box End Park offers camping facilities for participants, which can be booked directly through the park. Free parking is available on-site for all competitors.
• -- Sustainability and Support: Registration includes free event photos, custom-designed finisher medals, and post-race snacks. The event also partners with Alzheimer’s Research UK for charitable fundraising.
• -- Equipment: Wetsuits are typically required for the open water swim; rental options for day or season use are available through the organizer's partnership with Zone3.
• -- Transfer Policy: While refunds are not provided, ATW allows entries to be transferred to any future ATW event up to 48 hours before the race start without requiring medical proof.

Regional Context and Environment:

• -- Location: Box End Lakes is situated in Kempston, just outside of Bedford in Bedfordshire. The site is a repurposed aggregate quarry that has been transformed into a premier water sports destination.
• -- Water Quality: The lakes are spring-fed and renowned for their clarity and cleanliness, providing one of the most pleasant open-water swimming environments in the UK.
• -- Cycling Terrain: The cycling leg explores the Bedfordshire countryside, which is characterized by undulating hills and rural lanes. While the roads are described as "fast," athletes should be prepared for typical British country road surfaces.
• -- Climate: In late May, the East of England generally experiences spring conditions with average daytime temperatures ranging from 12°C to 18°C. Water temperatures in the lake typically hover around 14°C to 16°C, making wetsuits a standard choice for thermal protection.

The ATW Centurion 100KM Triathlon 2026 offers a professionally managed, high-quality multisport experience in a picturesque setting, making it a firm favorite for endurance athletes across the United Kingdom.