Bayhorse was built around silver mines that were active from 1882 to 1897 and again from 1917 to 1927. The mine/mill/smelter building pictured below was built in 1882. Bayhorse had emptied completely by the late 1960s. Bayhorse's private owner protected it for the following decades but did little to maintain its structures. The townsite was acquired by the state of Idaho in 2006 and opened to the public in 2009. It is now part of Idaho's Land of the Yankee Fork State Park.
So far the state has done almost no restoration work on any of the structures in Bayhorse. There are maybe a dozen building left in town in varying states of decay and disrepair. The structures and ruins are fenced and visitors are confined to walkways. The state has added informational signs, a pit toilet and a nice paved parking area. The road to Bayhorse is gravel. Parts of that road might be treacherous for an RV but are fine for any other kind of vehicle. A volunteer lives on site in an RV. There is a $5 self-pay fee to use the site. It's a small but interesting site to walk around.
No camping is allowed in the area immediately around Bayhorse but there is a developed BLM campground 5 miles away on highway 75. Sites at BLM's Bayhorse campground are $10 a night. There are several National Forest Service campgrounds further up Bayhorse Creek Road and a few free camping areas along the side of highway 75 west of Clayton. For me Bayhorse was the most interesting of the sites that make up the Land of the Yankee Fork State Park. The other units of that park that I visited are the Yankee Fork Dredge, Custer ghost town and Bonanza ghost town. The Yankee Fork units of the park are about 45 miles west of Bayhorse.