aeking3, at least in Madrid, it's hard to combine "Young" and "Fun" in the same area because the "Fun" areas are SO EXPENSIVE to live in that it's not even FUNny.
They're expensive because they're often the OLDEST parts of Madrid but have some of the best nightlife.
As mentioned above, sections of La Latina are quite vibrant. Madrid de los Asturias area south of the Royal Palace and across the Calle de Segovia is a particularly favorite area of mine - nice and old and lots of cool bars/restaurants.
Also as mentioned above, Lavapies is a (relatively) MUCH cheaper area, also very charismatic in OLD Madrid but not at all particularly nice/safe as compared to other areas of Madrid.
Barrio Salamanca is quite quite nice, VERY VERY VERY expensive (mainly just houses) but not particularly interesting and little (if any) nightlife. This area is for rich dignitaries, politicians, and businessmen who commute everywhere by car from their garages. It's also a long walk to the FUN areas of Madrid.
Anyone else have suggestions? Saludos, MadridMan
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