Thank you to all: great list. Amazing that short heritage lines such as Peak Rail have two. On a forthcoming trip, I hope to travel Derby-Matlock but won't be there on a weekend, so can't 'do' PR, and on same day am endeavouring to fit in Crich Tramway Museum (which I am told is outstanding) and Ecclesbourne Valley Railway, so about five minutes at the Matlock terminus will be the extent of my stay (sadly).
I excluded Nene Valley Railway from plans as it appears to mostly use foreign locos that are not an authentic representation of how UK railways were 'in the day'.
To see two at Blue Anchor and Ramsbottom as one hopes too is great.
I hope trucks or cars don't smash these gates too often: this was a perennial problem in my state of Victoria, Australia. We had one interlocked set left at the major provincial city of Ballarat (Lydiard St) but a train smashed into them and they were replaced by standard boom barriers, sadly: