| Cairu | |
| Official Name: | Municipality of Cairu |
| Settlement Type: | Municipality |
| Coordinates: | -13.4869°N -39.0439°W |
| Subdivision Type: | Country |
| Subdivision Type1: | Region |
| Subdivision Type2: | State |
| Subdivision Name: |  Brazil |
| Subdivision Name1: | Northeast |
| Established Title: | Founded |
| Established Date: | 1608 |
| Leader Title: | Mayor |
| Leader Name: | Fernando Antonio dos Santo Brito |
| Unit Pref: | Metric |
| Area Total Km2: | 451.194 |
| Population As Of: | 2022 |
| Population Footnotes: | [1] |
| Population Total: | 17,761 |
| Population Density Km2: | auto |
| Timezone1: | BRT |
| Utc Offset1: | -3 |
| Postal Code Type: | Postal Code |
| Blank Name: | HDI (2010) |
| Blank Info: | 0.627 – medium[2] |
Cairu is a municipality in the state of Bahia in the North-East region of Brazil. The municipality consists of three islands: the Island of Cairu, which is only separated from the mainland by a narrow river; Tinharé Island, which has the dense tourist settlement of Morro de São Paulo to the north; and Boipeba Island.
The municipality contains part of the of the Caminhos Ecológicos da Boa Esperança Environmental Protection Area, created in 2003.
The Cairu region was home to a large population of Aimoré people. The Portuguese arrived in the area early in the 16th century and soon established a sugarcane plantation. Francisco Romeo, administrator of the Captaincy of São Jorge dos Ilhéus founded a small settlement in Cairu based on its mild climate. The settlers displaced the Aimoré and the settlement, known as the Vila de Nossa Senhora do Rosário do Cairú, was established in 1608. It was located on an elevation overlooking the Tinharé Channel, which leads directly to the Atlantic Ocean. The Franciscans arrived in 1654 to build the Convent and Church of Saint Anthony on another high point in the settlement. Cairu became a major producer of manioc flour and timber in the 17th century. The town was forced to contribute 166$000 annually for three decades to fund the rebuilding of Lisbon after the 1755 earthquake.
By 1911 the village consisted of five districts: Cairu, the village seat; Galeão; Gamboa; Morro de São Paulo; and Velha Boipeba. It was raised to city status in 1938.
Cairu is home to numerous colonial-period historic structures, some designated as Brazilian state or national monuments. The historic center of Cairu (Centro Histórico de Cairu) lacks state or federal protection, but is home to numerous historic homes, government buildings, and churches.
Cairu is served by Lorenzo Airport located in the district of Morro de São Paulo and by Fábio Perini Airport located in the district of Boipeba.
Portugal football international Liedson was born in Cairu.