On the evening of November 17, 1973, 17-year-old Roger Essem and four friends drove to Gitchie Manitou State Preserve in Lyon County, Iowa, for a campfire gathering. The group included a 13-year-old girl and teenagers Stewart Baade, 18, Dana Baade, 14, and Michael Hadrath, 15. Three brothers—Allen, David, and James Fryer—were in the park illegally poaching deer and, believing the teenagers had marijuana, positioned themselves on a ridge with shotguns and opened fire.

Roger Essem was struck first and killed instantly at the campsite; the other boys were chased, separated, and murdered during the attack. The lone female survivor was kidnapped and later sexually assaulted but provided detailed testimony that identified one brother and the truck used that night. The bodies of the Baade brothers and Michael Hadrath were found the next day; Essem’s body was found a day later at the original campsite. On December 1, 1973, the Fryer brothers were charged with four counts of murder, and subsequent trials resulted in convictions and life sentences for Allen, David, and James Fryer.

Does anyone have additional information about the victims or the location that could add context to this case?