In pre-Columbian times the land where the canton of Alajuela is today, was part of the Huetar Kingdom of the West; which was inhabited by native tribes, both North and South Sector, who at the time of the Spanish conquest were led by Chief Garabito.
The first time the name of the Lajuela is cited it's in the protocols of Cartago, in the will of doña Juana Vera and Sotomayor, widow of Sergeant Garcia Ramiro Corajo awarded in 1657. Later, in a deed of obligation issued in 1864, are mentioned again the place they call La Lajuela in the Barva Valley , near the Canoa River.
In 1777, the neighbors of La Lajuela and Ciruelas, having been served with notice to move to Villa Vieja (today's Heredia), requested the provisional construction of a public place of prayer, which was established in the house of Don Dionisio Oconitrillo (of Spanish origin), 30 meters north of where Alajuela's cathedral is today.
According to the Constitution promulgated in the Courts of Cádiz (Spain, May 19th, 1812), the first town hall of Alajuela was founded in 1813. On December 18th of the same year, the La Lajuela neighborhood obtained the title of town and it was called "Villa Hermosa", then it was called "San Juan Nepomuceno de Alajuela" and finally the title of city was granted on November 20th , 1824 conserving the name "Alajuela" which remains today.