https://portalsoflondon.com/ So I came across this blog the other day of various fictitious supernatural encounters in well, London. Though the stories cover other stuff like ghosts, cryptids, time travel shenanigans, etc. there are quite a few posts detailing alternate universe/history based ideas. Here are few interesting examples: https://portalsoflondon.com/2019/08/16/aurora-orientalis-the-bow-creek-utopia/ A man with faulty VR glasses glimpses a deserted mega city built along the Thames. https://portalsoflondon.com/2018/10/19/mist-shrouded-cities-the-newcourt-continuum/ A police helicopter sees an alternate London rebuilt after the fire of 1666 in a grid pattern in the morning fog. https://portalsoflondon.com/2018/04...house-of-uncommons-and-the-other-other-place/ The walls of Parliament occasionally give way to sinister worlds like a Roman style city and an evil mirror assembly. Side note: I’ve never personally been to London or the UK in general, but I figured you guys might find this interesting.