One of the historic mansions in Newport, R.I. is going on the market for $12 million.

“Ker Arvor,” a restored Louis XV Revival-style house measuring about 12,500 square feet, was built in the 1930s, according to listing agent Kate Leonard of Lila Delman Real Estate International. With roughly 21 rooms, the house sits on 9.1 acres across from the Newport Country Club.