Oscar Niemeyer in Brasilia, Brasil

Oscar Niemeyer transformed Brasília into a modernist masterpiece during its construction as Brazil's new capital in the late 1950s. As chief architect working alongside urban planner Lúcio Costa, Niemeyer designed the city's most iconic structures, including the National Congress with its distinctive twin towers flanked by a dome and inverted dome, the Cathedral of Brasília with its hyperboloid structure of concrete columns reaching skyward, and the sleek Palácio da Alvorada presidential residence. His work in Brasília showcased his signature style of bold, sculptural forms that emphasized curves and dramatic concrete shapes, famously declaring his preference for "the free and sensual curve" over rigid right angles. The city, inaugurated in 1960, became a UNESCO World Heritage Site and stands as Niemeyer's most ambitious and comprehensive architectural achievement, demonstrating his vision of how modernist architecture could shape not just buildings but an entire urban landscape. His designs for Brasília remain influential examples of mid-century modernism and helped establish him as one of the 20th century's most important architects.