What is mission san Diego de alcala made out of?

Mission San Diego de Alcalá was constructed primarily using adobe bricks. Adobe is a traditional building material made from a mixture of clay, sand, straw, and water that is formed into bricks and dried in the sun. The mission's walls, structures, and living quarters were constructed using this adobe technique, which is known for its thermal properties, providing insulation from the hot and cold desert climate of San Diego.