In colonial times, Monserrat was the political, economic, social and cultural center of the city, and still packs history in at every turn. Best explored on foot, the zone buzzes at night with locals and adventurous foreigners trying out their moves at milongas, or tango halls. Check out custom-designed guides to the top milongas in Buenos Aires by Nile Guide's local expert: BA's Best Tango Venues and 24 Hours of Tango.