El Santuario de Chimayo is an important pilgrimage church located in the hills of Northern New Mexico. Initially a Catholic chapel was built on the site to serve the Spanish Mission, but was replaced by the current church in 1816. During Holy Week each year, about 30,000 faithful make the trip for a pilgrimage.
Walking the grounds, there are several small shrines and fences where visitors have left crosses. There’s also a room (El Pocito) in the rear of the church where dark soil from the area is blessed and taken by visitors for hopes of healing or cures. Although the room is filled with crutches and wheelchairs from visitors deciding they no longer needed them, the church hasn’t officially opined on whether any miracles have occurred as a result.
The Church has a website with a lot more information on the history and some of the specifics of the location – Sanctuary of Chimayo.