West Plains Opera House
100 West Main Street
West Plains, MO 65775
There doesn't seem to be much on the web about this old facility. It was divided into a restaurant and event facility when I visited in 2013. Like many such named 19th century facilities, it probably never hosted European grand opera productions as the term opera is commonly used today. A local group performing opera scenes there in 2012 speculated that they were the first actual opera production.
If it don't say Boeing on it, I ain't going on it.