Santa María Tonameca is a town and municipality located on the southern coast of Oaxaca, Mexico, about 268 km from the capital city of Oaxaca. It is part of the Pochutla District in the east of the Costa Region. It is a very rural area, which is best known for the beach communities of Mazunte, San Agustinillo and La Ventanilla. The National Turtle Center, a research center and aquarium is located in Mazunte, along with conservation centers for butterflies and iguanas. The town itself is the site of the largest annual festival in the area, celebrating the rescue of a cedar image of the Virgin Mary from the rubble of the town church after an earthquake on 11 May 1870.

Oaxaca is a state in Southwest Mexico that is divided into 570 municipalities, more than any other state in Mexico. According to Article 113 of the state's constitution, the municipalities are grouped into 30 judicial and tax districts to facilitate the distribution of the state's revenues. It is the only state in Mexico with this particular judicial and tax district organization. Oaxaca is the tenth most populated state with 4,132,148 inhabitants as of the 2020 Mexican census and the fifth largest by land area spanning 93,757.6 square kilometres (36,200.0 sq mi).