I've had these challenges on my radar for a while now - I find it interesting how some I easily qualify for but others I'm miles off. I picked up a couple of them last year while visiting my daughter at Bristol Uni. Today I was on the way back from another visit (we'd been to see The Stranglers at Tyntesfield).
I met a dog walker on the walk here with four Alsatian puppies - all very bouncy. The cache was a quick find. Its good to see such a big cache - most regulars I come across now are no more than litre sized
I'm currently on 1606 unknown caches as can be seen on my profile. However I'll also attach a screenshot here as proof.