Something went wrong with my post above. But nevermind. That's Alton Towers in Staffordshire, UK. That building plus some CGI could make some decent Arkham Asylum.
Plus: This old castle lies within a theme park of the same name (http://www.altontowers.com
). So if the film crew needs some Joker scenes in an old theme park/carnival - they could also do it right there.
And - this place is not far away from here: