ATW Watford Half Marathon & 10k

Welcome to the Watford Half Marathon, 10K & Fun Run, a thrilling event set to take place on Sunday, February 7th, 2027, starting in the picturesque Cassiobury Park!
Join us for a day of running, community spirit, and exciting experiences that has been taking place for over 40 years!

IF YOU WANT 2000 REASONS TO ENTER THE WATFORD HALF MARATHON THEN YOU'LL BE PLEASED TO READ THAT ONE LUCKY COMPETITOR CHOSEN AT RANDOM WILL WIN A £2000 CASH SPOT PRIZE!

The day kicks off with a 1.8km Fun Run around the Park, giving parents and supporters a great chance to cheer on their little athletes.

The multi-terrain 10k starts off alongside the Half-Marathon participants, leaving the park and heading on to traffic-free roads. The route diverges around the 4k mark, guiding you down to the peaceful towpath of the Grand Union Canal. For the next 3k, enjoy the calm of the water's edge before immersing yourself in the quiet beauty of woodland trails. The final stretch takes you past event HQ, where cheers from your supporters will carry you across the finish line. The 10k has no cut-off time - so you can run, jog or walk at your own pace. Entries to the 10k are limited, and it sold out in 2026, so dont miss out!

The Half Marathon will start in Cassiobury Park and follows fully closed roads, venturing into the country lanes behind the Grove Hotel and Golf Course. Runners will pass through Bucks Hill, Commonwood Common, and Chandlers Cross before looping back to the stunning Cassiobury Park. There is a cut off of 2 hours 45 minutes to the 11 mile point for the Half Marathon, as the roads will be reopening.

This Half Marathon features the Hertfordshire Vets half marathon championships. To be eligible, you must have been born in Hertfordshire or been a resident for 9 months. Please state in your eligibility during the registration process.

Lead Car & Cycle Escort: The event will be proceeded by a lead car and cyclists, ensuring a smooth and safe journey for all participants throughout the course.

Racecheck Gold Award: This event has proudly earned the 'Racecheck Gold Award', a prestigious, independent accolade given to running events scoring over 96% in participant reviews.

Musical Entertainment: Enjoy the rhythm of the course with music, including the beats of our amazing drummer, adding excitement and motivation to your run!

Ideal for London Marathon Training: Whether you're gearing up for the London Marathon or seeking a challenging yet scenic route, the Watford Half Marathon is the perfect opportunity to test your skills and stamina.

Spot Prize: One lucky Half Marathon runner stands a chance to win an incredible spot prize of £2000! Will it be you?

Vibrant Event Village: Embrace the lively atmosphere at our event village, filled with activities, stalls, and a fantastic community spirit.

PB Pacers: We will have pacers in both the 10K and half marathon. When you get to the venue, please look out for our pacers with their flags and feel free to join then for the event.

Finish Line Goodies & Unique Medal: Celebrate your achievement with special finish line goodies and receive a one-of-a-kind medal as a testament to your accomplishment.

Free Photos: Capture the unforgettable moments with free professional photos, preserving memories of your incredible run.

Professional Commentator: Feel the excitement as professional commentators set you off at the Start and cheer you on at the Finish line, making your achievements even more memorable.

Don't miss this opportunity to be part of an exhilarating event that combines fitness, fun, and community support. Register now for the Watford Half Marathon, 10k and Fun Run and be prepared for a day of thrilling runs, fantastic prizes, and a vibrant celebration of achievement!

The Family Fun Run is a 1.8km run open to all ages (under 8’s must be accompanied by a full paying adult) and stays within Cassiobury Park.

Protein Rebel is our official nutrition partner – A UK-based natural nutrition brand that helps runners fuel, hydrate and recover without the unnecessary ingredients that can be hard on your gut. Protein Rebel’s award-winning maple syrup energy gels will be available to all half marathoners at the aid stations, keeping you fuelled throughout the 13.1 miles. A discounted half marathon bundle and other exclusive offers (including 15% off gels and electrolytes using code WATFORD15) are now available on Protein Rebel’s website.

Purchase your 2027 event t-shirt HERE

Read reviews on Racecheck



Charity - Join us in making every stride count by raising money for our partner charity, Alzheimer's Research UK - your run will not only challenge your limits but also change lives, one step at a time, for a cure. Opportunities to donate and fundraise will appear at checkout.

ATW Transfer & Refund Policy

At ATW, we understand that sometimes plans change. While we do not offer refunds or transfers to another person, we provide a hassle-free event transfer option for those unable to attend their booked event. If you are unable to participate in your scheduled event for any reason—including injury, illness, pregnancy, bereavement, or other unforeseen circumstances—you can transfer your entry to any future ATW event. There is no proof required, we trust you!
Even better news, transfers can be made all the way up to 48 hours before your original event date.

ATW Community

At ATW we think of our participants as a community and we love to hear about the community's dreams and achievements.

If you'd like to share those dreams and achievements you can do so on any of our social media platforms. Equally if you'd like any advice about your upcoming event you will almost certainly find someone who can provide some guidance.

Links to all our social media platforms are at the bottom of the page, including to our ATW Chat Facebook group, which might be the most interactive platform if asking for help.

Event Organiser

ATW was established in 2011 by James Shipley. We have now become a national events company in the UK, specialising in Running, Triathlon, Duathlon, Aquathon, Cycling, Swimming and all permutation of swim-bike run events. With over 40,000 entries a year ATW has become a firm favourite amongst people who are determined to Dream, Believe and Achieve.