One of Antoni Gaudí's least-visited works, an homage to Catalan patrimony that mixes neo-Gothic with Modernista forms.

One of Europe's largest supercomputers is housed inside of a disused chapel.

A cemetery in Barcelona's Poblenou district is home to this touching funerary statue, which depicts death in the form of a winged skeleton.

A temple to modernity, tucked away amid Barcelona's more well known museums.

This former Baroque palace on the historic Calle Montcada is a rare architectural gem and was once the meeting place of an aristocratic scholarly society.

Week-long block party becomes a competition for the best decorated street.

The largest Art Nouveau complex in the world is a Barcelona hospital with a 600-year-long history.

Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

A beautiful but toxic fountain of mercury.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

This semi-secret storybook hedge maze is also the oldest garden in the city.

The only natural cave bath in all of Europe.

A peculiar museum that includes many drunken tales, a drunk driving simulator, and much more.

One of the newest mosques in a city filled with thousands.

This crucial gathering spot along the "hippie trail" still displays old notes between traveling beatniks and backpackers.

A meow-velous tribute to a beloved street cat, made famous on the internet.

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

A marvel of Byzantine engineering under the streets of Istanbul.

This ice cream parlor serves scoops of flavors like rakia, medlar, and poppy seed.

Different sections of the Zemun Fortress were built in the 14th and 15th century as a response to the advance of the Ottoman Empire.

This only museum in the world dedicated solely to mushrooms.

This 135-year-old weather station studied the effects of the climate on human health.

This scale model of our solar system hid in plain sight for years before a physics team sought out all the planets.

A relic from the Industrial Revolution got a second life as a contemporary performing arts space.