I entered one of the earlier Castle Triathlon Series events. As you can see from the image they are huge events and, from my personal experience, very well organised.
I’m not sure I can fit one in myself next year but if you’re filling up your race diary now then an (Half-) Iron-distance from Castle is a cost-effective taster. Hever is a great location in a beautiful and challenging part of the country.
Last Updated on 11 October 2025 by the5krunner
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tfk is the founder and author of the5krunner, an independent endurance sports technology publication. With 20 years of hands-on testing of GPS watches and wearables, and competing in triathlons at an international age-group level, tfk provides in-depth expert analysis of fitness technology for serious athletes and endurance sport competitors.
