Capital city of Piauí, is usually used as starting point to visit 2 important National Parks located in Piauí: Parque Nacional de Sete Cidades (Seven Cities National Park) and Parque Nacional das Capivaras located
The name Teresina is a tribute to Lady Teresa Cristina, Empress of Brazil, wife of D. Pedro II. Lady Cristina was so admired in Piauí that another city, Imperatriz, was named after Her. Likewise, Teresópolis, city in Rio de Janeiro, was named in homage to Lady Teresa Cristina.

Teresina was the first city in Brazil to be planned. It was designed in 1852 by a master builder in the form of a chessboard. Located 622 km far from Fortaleza, Teresina is the only capital of Brazilian northeast which was not built by the coast; because of this, Piauí is the only Brazilian State which is more developed in the interior than on the coastline.

Situated at the mouth of the Rivers Parnaíba and Poti, it is known as the green city because all its streets and avenues are lined with trees, mainly mangoes.
These two rivers provide the city with beaches that are very popular during the period of drought between May and November when the waters retreat and form lakes surrounded by sandbanks.
The city also has beautiful sunsets and various monuments, in particular the church of St. Benedict built in 1886, with carved timber doors, and the 4 de Setembro Theatre in neo-classical style, inaugurated in 1893.

Dating from more modern times is the church of Our Lady of Lourdes, built in 1961 and decorated with sculptures by the masters Dezinho and Expedito, the most famous sculptors in Piauí, and the gardens of the Karnak Palace - seat of state government - designed by Roberto Burle Marx, regarded as Brazil's greatest landscape architect.

The Museu Histórico do Piauí (Historic Museum of Piauí) has a large heap of fossils and ancient maps, most of them collected at the Parque Nacional das Capivaras, also in Piauí, the largest archaeological site in Brazil.
The Parque Nacional de Sete Cidades (Seven Cities National Park), 180 km far from the capital, has rocky formations that resemble seven cities, with streets, public squares and monuments.

As it is located near the Equator, high temperatures in Teresina vary between 26 and 40 degrees Celsius (79 to 104 degrees Fahrenheit) throughout the year, with the lowest temperatures occurring in the first 5 months of the year. The hottest time of the year is October through December. Humidity is high year-round.