One of the coolest thing I saw in Buenos Aires was the Cementario de la Recoleta. It is an amazing 'city of the dead' full of elaborate crypts to the rich and famous of Buenos Aires. Wandering around the lavish marble tombs reminded me of Vanitas paintings (Vanitas are a 17th-century Dutch genre of still-life painting containing symbols of death or change as a reminder of their inevitability for everyone, even the most wealthy and powerful).
The view inside the tombs is just as lavish as the exterior, many of them are adorned with marble and bronze sculptures. Looking into the tombs was often a touching sight, with photos of smiling faces in their happiest days, surrounded by flowers placed there by their loved ones.