Zip Line Your Way Across Town

"[A] new kind of urban tourism, where you don't talk guided walks or buy tickets for double-decker buses: you ride zip lines above Notre-Dame cathedral and down Fifth Avenue, getting up close and personal with architectural ornament at a level of detail you would otherwise never have seen.
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In the same way that you can take, for instance, Entourage-themed bus tours of Los Angeles, you could take Spiderman-themed zip line tours of New York.

You call up Canopy Tours and ask them to price-out the entirety of Chicago. Or Istanbul. (At the very least, they could map it).

Zip lines through the London financial district.

Zip lines through the sandstone arches of Utah.

Zip lines through Angkor Wat.

A Zip Line Olympiad across the domes and spires of central Europe."