One of Amsterdam's narrowest houses is located right across the canal from its widest.

The first firefighters museum in southern Spain is ironically located in an old textile mill that burned down in 1985.

This impressive former palace contains a hidden gem for fans of modern sculpture.

An abandoned socialist utopia built in the late 19th century.

This Gothic church houses ornate royal tombs and a magnificent gilded altarpiece.

In an arboretum with hundreds of memorials to the fallen, this one might be the most poignant.

This beloved ancient tree is the pride of this city center.

An archaeological museum squeezed into a narrow 15th-century gate tower accessed only by a spiral staircase.

A section of a historic wooden trestle viaduct is preserved next to the railway line it once carried.

This Victorian footbridge over the River Tees was originally built to carry water from the high moorland to the industrial towns on the coast.

Public art now takes pride of place on the site of one of County Durham's last deep coal mines.

Locals affectionately dubbed this World War I memorial "Tommy."

This industrial museum is based on one of the oldest standing iron forges in the U.K.

A repurposed railway tunnel with otherworldly acoustic characteristics.

This amazing example of Valencian Art Nouveau looks more like a cathedral than a public market.

The magnificent sanctuary is Spain's first purpose-built structure of its kind.

This petite cutlery factory sits on the foundations of a defunct gasworks.

This magnificent brick dome was made with an unusual design method.

Locals use these rock pools and waterfalls for swimming and cliff diving.

Cliffside houses provide a spectacular view from their perch above the valley.

This museum is known as the "Land of the Dinosaurs," but its full-scale dino models are just the start.

This uniquely shaped 17th-century structure comes alive in early September.

A lovely look back at the manufacture and use of paper in all its forms.

This reconstructed ancient fort was home to one of the few horse training rings in the Roman Empire.