Sky Costanera is the observation deck of the Gran Torre Santiago, the tallest building in Latin America, in the Costanera Center complex in Las Condes. The deck sits at 235 metres above street level and gives a 360-degree panoramic view of the city — the most complete aerial perspective available without a helicopter.
The best time to visit is a clear winter morning (June–August) when cold fronts have cleared the smog that tends to settle in the Santiago basin during spring and autumn. In summer the air can be hazy. Book tickets online to skip the queue; the experience takes about an hour including the elevator rides. The adjacent Costanera Center mall has restaurants, a cinema, and everything else you might need to fill out the afternoon.