Art Nouveau Tour of Barcelona. This is Casa Batllo, designed by Gaudi. Spain was not drawn into WW I and as such during that time, had prosperity. As as result, there are over 400 Art Nouveau structures in Barcelona.
This Guell Park in Barcelona, Spain it is an incredible park full of the coolest mosaics. According to Rick Steves this park was originally designed as a sort of Gated Community. The project flopped as an upscale housing area and is now a fabulous park.