San Mateo is the number 4 canton of the province of Alajuela in Costa Rica. It is located 31 kilometers east of Caldera de Esparza, 44 kilometers southwest of the capital city of the province of Alajuela, and 58 km from the national capital of San José. It has an extension of 125.9 km² and is divided into 4 districts. Its limits are to the east with Athens, to the north with San Ramón and Esparza, to the west with Esparza, and to the southwest with Orotina. It was founded on August 7,1868. Its head is the city of San Mateo. According to the 2011 National Census, the population of the canton was 6,136 inhabitants, of which 5.3% were born abroad.
The same census highlights that there were 1,834 occupied dwellings, of which, 55.2% were in good condition and there were problems of overcrowding in 3.2% of the dwellings.26.3% of its inhabitants lived in urban areas. Among other data, the level of literacy in the canton is 97.7%, with an average schooling of 7.5 years. The same census details that the economically active population is distributed as follows: Primary Sector: 31.9%. Secondary Sector: 10.2%. Tertiary Sector: 57.9% For the year 2012 it had a very high human development index according to the United Nations Development Program, being one of the cantons of the country that recorded the highest gains in this index. The economy of San Mateo is basically agricultural, being of importance the fattening cattle, due to the extensive plains of the canton. As far as agriculture is concerned, the cultivation of coffee and fruit trees, especially cashew, is important.
In pre-Hispanic times, the territory of San Mateo was inhabited by natives of the huetares nation. In a place that the Spaniards denominated as Valle de la Cruz was the main residence of King Huetar Garabito. In 1574 an indigenous reduction called Santa Catalina de Garabito was established in that same place, which subsisted until the second half of the 18th century and was located in the vicinity of the stream known today as Garabito Creek. From 1820 gold mining was developed in the Montes del Aguacate, whose boom occurred especially in the decades of 1820 and 1830. Later, San Mateo was developed thanks to the fact that the highway between San José and Puntarenas passed through its territory., later, the railroad to the Pacific.
Among the touristic sites of the canton are the old Aguacate Mines, the Damas Bridge over the Jesús María River, which connects with Esparza, a natural spa in the district of Desmonte. The city of San Mateo is a transit point to the beaches of the Central Pacific of Costa Rica along the route of the Montes del Aguacate, two hours from San José.