An ancient system of freshwater caves filled with animal bones, including that of species long-extinct.

One of the earliest large-scale "hyper" roofs in the U.K. is now a derelict roadside attraction.

A striking 500-year-old mansion provides an unexpectedly sublime home for live deer and a menagerie of exotic stuffed animals.

Hidden in a grotto 26 feet below Nottingham's oldest hotel, this stylish subterranean drinking den is notoriously hard to find.

This quirky shop on a former farm is full of weird and wonderful oddities and antiques.

A gorge full of caverns where early humans lived alongside cave hyenas, giant mammoths and wooly rhinoceroses.

This centuries-old canal known as the Cuckoo Dyke has a staircase of locks suitable for a giant.

What looks like missing grout is actually an old pub's peephole.

This mummified mermaid corpse is an aquatic curio that was eventually revealed to be a fake.

An abandoned 18th century manse looks like something out of an Indiana Jones movie.

A kaleidoscopic warehouse-maze of handmade neon signs.