Alzheimer’s Research UK stand for everyone affected by dementia. By fundraising for them you can take part in a sport you love, at stunning locations, whilst helping to raise research funds that benefits all of our futures.

BulkSMS provide competitors with essential race information directly to their phones, ensuring everyone stays informed. As a leading SMS messaging service provider, BulkSMS offers seamless two-way communication from any internet-enabled device.

TTH specialise in innovative coaching for individuals and groups. They offer coaching support to our athletes including race specific training plans, pre-event training sessions and a virtual training club.

Founded by two-time Olympic champion Alistair Brownlee, trufuels provide fueling solutions that eliminate digestive distress and flavour fatigue, empowering athletes with only essential nutrients for optimal performance, recovery, hydration, and daily nutrition.

Take the hassle out of travelling with a bike and hire one for race day. On Your Bike's team of mechanics will be on hand for any fitting adjustments, pedal changes or installation of extra parts that you may want.

Need to hire a wetsuit? This is really easy, quick and affordable solution for making sure you have a high performance, technical wetsuit for race day. Simply enter the discount code CASTLE10 on the check out page to get 10% off!

Winner of 'Best in Test' sports bras three times! A female empowerment sportswear brand revolutionising sports bras with their unique Overband® Technology.

Get stocked up on BeetActive and CherryActive concentrates, the perfect natural pre and post nutrition pairing enjoyed by leading endurance athletes, football, rugby and Olympic teams.

Make sure you're covered for any unforeseen circumstances. Yellow Jersey have a number of different options for event day cover, bike damage or theft and reimbursement due to injury.

Look the part when you're training in one of our Castle Race Series t-shirts. Share your photos using #CastleRaceSeries so we can see you in action.

High Performance for Athletes — UVA & UVB protection from the sun, Pelotan is lightweight, breathable & sweat resistant. Providing high performance protection for athletes so you can do more of what you love.