This building contains a door only used by members of the royal family.

This site was once home to Henry VIII and Elizabeth I.

The last vestiges of a magnificent Victorian-era train station can be found in this pub.

This sprawling, Brutalist estate feels like a city within a city.

Children's hospital in London that operates on royalties received from Peter Pan, which J.M. Barrie signed over in 1929.

This medieval church tower has maintained its clockworks since the 16th century.

A gallery specifically dedicated to the botanical illustrations of a remarkable traveling lady.

Museum dedicated to the UK's first charity for abandoned children, with keepsakes of the mothers who left them behind.

An eccentric 18th century naval officer built a ship's quarterdeck on his roof, the inspiration for Mary Poppins's "Admiral Boom."

Giant, friendly pelicans in Central London, the most unlikely of places.

Hidden beneath the streets of London is a secret subway that only carried mail.

An easily overlooked stretch of ornate window fronts and gaslight lamps that could be right from the pages of Dickens.

A charming 17th-century alley is lined with secondhand bookstores and antiquarian shops.

A small museum built by a family that survived the Siege of Sarajevo.

This unique museum focuses on the Siege of Sarajevo through children's eyes.

There's a mini version of Iguazu Falls hidden in the Balkans, and it's got a rope swing.

An ancient knight and a symbol of the city's freedom.

Gargoyle head that brings good luck.

Picturesque basketball courts sheltered by historical defensive walls and with an enviable sea view.

A giant earring-wearing, poker-waving elephant statue stands in a Viking longboat in Kirkby town center.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

This marine reptile was discovered by one of the 19th century's greatest fossil hunters.

Order bagels and lox from an iconic Jewish delicatessen with nearly a century of history behind it.

The silly symbol for an underground protest group is now scattered around the city.