Five sultans and their families rest in eternal splendor, teeming with overlooked beauty and drama.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

A small etching on the white marble parapet was written in runic script by a Viking mercenary.

The ornate miniature mansions were built for Istanbul's feathered residents.

A marvel of Byzantine engineering under the streets of Istanbul.

Royals, rebels, and artists have all conversed at this grand 19th-century Viennese coffee house.

A magnificent collection of imperial armor and weaponry.

This series of Baroque passageways in Vienna's cultural center mix old architecture with modern art.

The Habsburgs' royal collections of art and wonders.

Beautiful Austrian natural history museum with carved ceilings and row after row of ancient taxidermy.

The beautiful baroque library of the Hapsburg empire.

A mountain pass in Bulgaria's Balkan Mountains was the site of four historic battles.

A magnificent, glittering building tucked into a tiny Bulgarian mountain town.

UNESCO-protected ancient burial ground.

An abandoned saucer-shaped monument in the Bulgarian mountains.

This ancient theater, restored in the 20th century, lives on as a venue for dramatic and musical performances.

The mummified right fist of a 1,000-year-old saint-king sits inside an ornate golden reliquary.

Museum dedicated to the terror regimes of Hungary.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

This elaborately decorated, fairytale-like Romanian royal palace is one of the most striking castles in Europe.

This metro station doubles as an unintentional paleontology museum.

This communist behemoth is the heaviest building in the world and a legacy of a brutal regime.

Sofia's legislative center is continuously reinventing itself.

"Holy Wisdom" overlooks the city that became its namesake.