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Join the Mariners Mile Swim on September 27, 2025, for a scenic and supportive open water challenge in Hertfordshire’s Lea Valley. Perfect for swimmers of all levels, this event combines nature, sport, and community in a memorable way.
Join the Mariners Mile Swim on September 27, 2025, for a scenic and supportive open water challenge in Hertfordshire’s Lea Valley. Perfect for swimmers of all levels, this event combines nature, sport, and community in a memorable way.
Book with Herts Young Mariners Base
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Operated by Herts Young Mariners Base · Cheshunt, England
The Mariners Mile Swim Event takes place in the expansive Lea Valley at the Herts Young Mariners Base (HYMB) in Cheshunt, Hertfordshire, offering a unique chance to experience the thrill of open water swimming amidst scenic surroundings. Scheduled for September 27, 2025, this event caters to swimmers of all skill levels, with distances designed to challenge beginners while providing a rewarding experience for seasoned athletes. As you step into the cool, clear waters of the Lea Valley, you'll be surrounded by a landscape dotted with lush greenery and gentle ripples, making each stroke a move through nature itself.
HYMB’s location is a favorite among local outdoor enthusiasts and families alike, partly due to its commitment to community and environmental sustainability. The entire event emphasizes accessibility and health, with participants receiving medals and supporting Cancer Research UK through a portion of the fees. The swim course boasts a straightforward yet exhilarating route along the river, offering striking views of the Hertfordshire countryside and attracting a diverse crowd eager to test their endurance.
This event isn’t just about competition; it provides a space to connect with fellow open water swimmers, share tips, and enjoy a day outdoors immersed in nature. The Lea Valley’s calm waters, coupled with the manageable distances, make it ideal for those looking to dip their toes into open water swimming or push for a personal best. Whether you're a local or traveling to Hertfordshire for the weekend, the Mariners Mile Swim is a standout event in this vibrant outdoor scene. Finish the race to a community of cheering supporters, knowing you've experienced a truly refreshing outdoor adventure that combines sport, nature, and charity.
The Herts Young Mariners Base’s commitment to promoting outdoor activity and environmental consciousness adds to its appeal, making every swim here feel purposeful and invigorating.
easy.
1–2 hours.
Swimmers should have a basic level of cardiovascular fitness and comfort in open water.
Yes, the event is open to swimmers of all skill levels, including beginners.
Early registration is recommended and can be done online before the event date.
Swimmers are typically given a 1-2 hour window to complete their distance.
Yes, trained safety personnel and support boats are present during the swim.
There are safety boats and crew support along the course to assist if needed.
Yes, HYMB offers changing areas and basic shower facilities.
Lea Valley has been a vital waterway for centuries, historically supporting trade and recreation, now serving as a popular open water swimming spot.
HYMB emphasizes sustainable practices, such as river clean-up initiatives and eco-friendly event management, to protect this natural resource.
Herts Young Mariners Base is an outdoor water activity centre located in Cheshunt, Hertfordshire, in the Lea Valley. The base runs a range of supervised lake-based activities for young people and adults, including sailing, canoeing, kayaking, stand-up paddleboarding (SUP), raft building, fencing, archery and climbing. Herts Young Mariners Base offers structured courses and one-off sessions: RYA Stage 1 three-day beginner sailing courses for children; BSUPA Level 1 “Ready to Ride” two-hour SUP introductions; coached canoe and kayak sessions for adults; and regular adult paddle sessions for experienced participants. The venue hosts organised events such as the Mariners Mile Open Water Swim and monthly “Adults Come and Try Activities” evenings. The Mariners Mile is an open water swim event held at HYMB in Cheshunt, with distances for different abilities and a minimum age of 14 for participants; a portion of the event fees supports Cancer Research UK. Adult swim sessions and coached paddles run on set evenings and weekends, with changing rooms and refreshments available on site. Herts Young Mariners Base uses qualified instructors for coached sessions and accredited courses, and schedules beginner-focused and skill-development opportunities for different ages and abilities. The base operates a mix of instructor-led courses and non-instructor-led sessions, providing options for certification, coached progression, or relaxed recreational use. Its location in the Lea Valley provides accessible open water and flat-water environments suitable for learning, training, and organised events. Booking info, session times and entry requirements are on the base's event pages; check before attending for exact details.
Book with Herts Young Mariners Base