This 3,000-year-old “opium black fortress” towers over the ancient town named after it.

The Dublin sea wall draws walkers, photographers, and fishing enthusiasts.

A two-storey cabinet of wonders filled with the bizarre, the macabre, and the downright uncanny.

The modern birthplace of Irish freedom.

These gigantic skeletons tower over visitors and provide insight into the creatures that once ruled over Ireland.

The block of aged dairy is probably still edible after 2,300 years in a peat bog.

The house where the writer spent his formative years.

The 19th-century pharmacy (now a used bookstore) was featured in James Joyce’s "Ulysses," and has changed very little to this day.

This permanent collection of preserved bodies taken from Irish bogs is one of the leading authorities on such morbid mummies.

The comedy and tragedy of Oscar Wilde is preserved in a Dublin park, captured in a sculpture of colorful stone.

This breathtakingly beautiful botanical garden is home to a mob of wonderful wallabies.

An awe-inspiring giant blue whale jaw bone stands in the center of this Dutch island.

A rare double mill nestled along the banks of the Aa river.

This old KLM airplane cut into three parts was transformed into an eclectic airport gift shop.

A late-medieval Dutch castle with trick fountains in its whimsical water gardens.

Amsterdam's former hotspot for public executions and dissections.

This massive mural by famed pop-artist Keith Haring was hidden for almost 30 years until its 2018 rediscovery.

A public urinal so pretty, it was declared a national monument.

This bird-loving brewery is situated in an old municipal bathhouse, nestled beside a 300-year-old windmill.

This cheese shop also houses a museum devoted to Dutch dairy.

A Dutch passageway's artistic, aquatic-themed makeover pays tribute to the capital city's famed waterways.

This historic Amsterdam bar used to accept sailor's monkeys as payment.

An ancient passage filled with stalls selling used books, once frequented by Vincent Van Gogh.

Visit an imposing 13th-century Transylvanian citadel lurking not far from the region's more heavily touristed attractions.