Must See - Things to do in Kielder

Kielder Waterside - about half way down the reservoir on the south-west shore. There is loads of stuff to do here - water-based activities, segways, archery, mini golf etc. https://www.visitkielder.com/visit/visitor-centres/kielder-waterside/
The Bird of Prey Centre at Waterside https://www.kielderbopc.com/
Hire bikes from Team Cycles at the north end of the reservoir near the castle. Cycle on the trails around the lake and through the forests. https://www.teamcycles.com/pages/aboutus/
Kielder Castle - there are some lovely short walking trails to do from here, usually some themed ones too if you have young children https://www.visitnorthumberland.com/explore/destinations/scenic-spots/great-outdoors/kielder-castle-forest-park-centre
The Minotaur Maze - just down the hill from the castle - it’s not too complex, you won’t get lost for long!
The old Kielder Viaduct - about a fifteen minute walk from the castle towards the reservoir.
Children’s Playparks - the best one is at Kielder Waterside.
Dark Skies - simply amazing: no electricity, no light pollution, get wrapped up and spend all night looking at the stars. https://kielderobservatory.org/
Go on the ferry in search of ospreys! (summer only). https://bookwhen.com/kielderwatersideferry#focus=ev-sr349-20260801173000