The Old Spanish National Historic Trail passes through Arizona, California, Colorado, Nevada, New Mexico, and Utah. It opened a land route across 19th century Mexico between the Tierra Adentro, the fabled, yet isolated place that would become New Mexico, and California’s missions and burgeoning settlements. When he left Abiquiu, New Mexico for California in 1829 with 40 men and 200 pack mules, Antonio Armijo blazed a trail between the two colonies that had frustrated explorers for over a century. The Abiquiu party’s woolen blankets and tanned hides were welcomed in textile-starved California. In return, the horses and mules Armijo and his followers on the trail brought east would become the working stock for miners, American and Mexican military, and farmers from northern Mexico to the east coast of the United States.