The only two royal clubs to have disappeared in the UK were both ‘county’ golf clubs
The Royal Cornwall at Bodmin and the Royal Isle of Wight at St Helen’s, Bembridge
Also NLE is another once-celebrated nine-hole seaside ‘county’ course, the Merionethshire Golf Club at Fairborne, one of the founding members of the Welsh GU and once prominent enough to be cited in the chapter on Famous Courses in the Badminton Library volume on Golf.
Wasn’t Seaton Carew originally the Durham and Yorkshire GC?