Spanish prospector José Manuel Carrasco filed the first copper claim at what's now Santa Rita in 1799. By 1804, mule trains were hauling copper south to the Royal Mint at Chihuahua under contract — the first sustained mining operation in what would eventually become New Mexico Territory. The Kneeling Nun, the limestone formation rising above the pit, was the working landmark from day one.
What followed was 220 years of starts and stops. Apache raids closed the workings in the 1830s. The Confederacy briefly held the diggings during the Civil War. The Santa Rita Mining Company reopened in 1873, then sold to Phelps Dodge, then to Chino Mines, then to Freeport-McMoRan — the operator today. Through every owner, copper kept Grant County employed when nothing else would have.
The town of Santa Rita itself didn't survive. The pit kept growing until, by 1970, the whole townsite — homes, school, the Hurley railroad spur — had to be swallowed and relocated. Old Santa Rita is literally gone. Former residents still hold reunions; some can stand at the rim and point to where their kitchen used to be.
If you want to see the scale, the overlook on NM-152 just east of Hanover is free and open from dawn to dusk. Bring binoculars. The haul trucks look like toys from up there, but each tire is over twelve feet tall.