This striking church ruin is located in West Laramie, Wyoming
The structure is clearly that of a classic Gothic style church, which was constructed out of stone and cement. The structure of the church itself would tend to indicate that it was likely built in a classic Catholic church manner, which would indicate here that the church was likely built with a Catholic or Episcopalian congregation in mind, although its location might possibly indicate that it was built as a chapel for the Territorial Prison in Laramie. The structure is very old, and its been in ruins for as long as I personally can recall. It's now located on the grounds of a farm, but at the time it was built it would have been actually several miles outside of Laramie, and indeed it would have been at least three miles from the territorial prison.
This church is a mystery to me, and if anyone knows what it was, I'd appreciate knowing.