1 August - Yorkshire Day! - and Richmond Castle will awake from its slumbers and open its gates to visitors again. There'll be a few restrictions: you won't be able to climb the Keep (the central tower) but your legs will thank you for that; and you'll need to book in advance - but it'll be well worth it.
If you're a visitor to Richmond, you can't very well not visit the Castle... Booking details are here.
Welcome to Richmond Information Centre's website, the best source of information on this wonderful town. Take a look round!