Quiz a local on what the most well-known structures in town are and they'll probably mention Brasilia TV Tower. It's one of the first things that'll catch your eye when you start exploring.
This modern piece of architecture is in Plano Piloto, a destination that has loads going for it! Arena BRB Mané Garrincha, National Congress of Brazil, and Itamaraty Palace are other fine sightseeing opportunities close by when you're done at Brasilia TV Tower.