One of the largest and oldest caravansaries in Persia.

Modern-day cave dwellers carve elaborate homes out of volcanic debris.

The vertical-axis windmills of ancient Persia have been grinding flour for 1,000 years and counting.

Hydraulic systems in an ancient underground Iranian city.

A sophisticated astronomical tower built by one of the greatest Persian scholars of the Islamic Golden Age.

This ruined fortress was the stronghold for a persecuted medieval leader and his infamous Assassins.

A 1,500-year-old, 3-story subterranean city where ancient Persians took refuge in times of war.

Iran's colorful terraces are a rare geological masterpiece.

The skeletal remains of the famous hominid "Lucy" were found at this spot.

An ocean in the making, in the Ethiopian desert.

Ethiopia's "smoking mountain" is in one of the hottest regions on the planet and is home to two lava lakes.

The train platform where Jews were sent to concentration camps is now preserved as a Holocaust memorial.

Nestled in the heart of Milan is a real wunderkammer of morbid curiosities.

A space dedicated to contemporary art and culture, co-chaired by fashion icon Miuccia Prada.

An exclusive waiting room built for the royal family in the 1920s is hidden in Milan’s central station.

This curious building hides eclectic details like medieval gargoyles alongside naked angels and Art Nouveau mosaics.

Known as the "Queen of Beach Markets," Calangute epitomizes Goa's beach flea market scene.

The place of worship for Zoroastrians, Mumbai's Parsi fire temples use fire and ash for purification.

A peculiar idol to the Hindu King of Ghosts demands fine leather footwear in exchange for warding off evil.

This overlooked Japanese Buddhist temple is a respite from the bustle of Kolkata.

A fresco in this magnificent palace is said to have been the first depiction of the Taj Mahal's design.

This diminutive yet beautiful local stepwell once yielded enough water to irrigate the lush fields of the village.

In Mumbai, a bright blue synagogue is the largest one for the Baghdadi Jewish community in Asia.

This colorful colonial neighborhood in Panjim is one of the only Latin Quarters in Asia.