Be prepared to fall in love with the grand architecture of this library, a real paradise for every book-lover out there. This spot, though, is worth a visit anyway since it's undoubtedly an unmissable Victorian masterpiece.

Every visitor is aware of the existence of Amsterdam's red light district, locally referred to as De Wallen. Some head there straightaway while others prefer to walk around it — the choice is yours. The truth is, you will likely end up wandering through the area simply because of its location right in the city centre. The best way to get acquainted with the city's most notorious neighbourhood and discover its stories and secrets is by joining a walking tour. Follow your guide through winding cobblestone streets and narrow alleys as you learn the history behind Amsterdam's infamous adult destination. See, along the way, oddities like the world's first condom shop, the Museum of Prostitution, as well as little-known sculptures, and sex theatres.

The Struve Geodetic Arc is a chain of survey triangulation points that stretch from Hammerfest in Norway all the way to the Black Sea. The imaginary lines go through ten countries and over 2,820 kilometres. Carried out between 1816 and 1855 by the astronomer Friedrich Georg Wilhelm Struve, this survey represented the first accurate measuring of a long segment of a meridian, helping establish the exact size and shape of the planet. Sweden has seven measurement points and four of them are on the World Heritage List (on the mountains Tynnyrilaki, Jupukka, Pullinki, and Perävaara). The mountaintop unveils an expansive view.

If you're seeking to beat the Sonoran heat but still want to climb the mountainside, head to AZ on the Rocks. As Arizona’s largest indoor climbing gym, the Rocks has walls nearly 30 feet high. Aside from just having fun, the Rocks also offer an opportunity to work on climbing techniques and learn the ropes. Children under 18 must have a signed waiver allowing them to climb.