Alajuela is a canton in the Alajuela province of Costa Rica. Its head city is the provincial capital city of Alajuela. Alajuela was created on 7 Dece…Alajuela is a canton in the Alajuela province of Costa Rica. Its head city is the provincial capital city of Alajuela. Alajuela was created on 7 December 1848 by decree 167. Alajuela has an area of 391.62 km² and a mean elevation of 942 m.