This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

The oldest stone house in Paris was built by its most famous alchemist.

Abandoned railway line circling the city of Paris.

France's most famous cemetery, with some of its most curious tombs.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

This former school is now abandoned and a canvas for graffiti artists.

This 600-year-old tower was built as a comfy residence for cherished pigeons.

The ruins of a 12th-century Cistercian monastery can be found alongside World War II tank traps and pillboxes.

An ancient woodland that inspired a young J.R.R. Tolkien.

Inside this church is an obscure piece of art carved by the famous Alice Liddell.

This 19th-century island fort built to protect against an invasion by sea.

A medieval cave used to shelter local hermits now holds nearly 200 old Quaker gravestones.

This Norman castle was once the site of a Victorian-era prison, and now exists as a luxury hotel.

All that remains of the only English cathedral destroyed in the Protestant Reformation.

These bleak 800-year-old ruins were once the royal residence of choice for hunting in Sherwood Forest.

A 14th century castle built on the seat of a mighty giant.

This stone throne invites adventurers to observe breathtaking views of the Peak District.

The remains of the oldest synagogue in Britain lay forgotten for seven centuries, hidden under a humble shop.

These ruins of a medieval church are full of architectural mysteries.

The remains of the wrecked steam trawler can be found on the beach at low tide.

A theatre built to house the rowdy Oxford graduation ceremonies became the stage for a debate about God's existence.

The excellent acoustics of this natural amphitheater made it a popular preaching spot for the founder of the Methodist Church.

The National Railway Museum in York is the largest railway museum in the world, attracting almost 1 million visitors per year.

This Gothic castle-like portal is a testament to the amazing craftsmanship of the navvies who built the railway tunnel.