There are many instances of artwork created by pre-historic people around the world. In the Big Horn Basin there is a site called Legend Rock that has petroglyphs carved into the surface of a cliff. The earliesdt carvings are estimated to have ben made around 11,000 years ago and they are considered some of the oldest rock art in North America.
The images are carved in sandstone and portray bison, elk, deer, eagles, people and other animals. The Native American people report that medicine men would go on spirit walks and then carve what they saw into the sandstone. The petroglyphs have been carved in what's the called the 'Dinwoody' style which is only seen in the Big Horn Basin area. Most of the carvings portray scenes you would expect of people who hunt for food but there is one interesting image in one of the sets of petroglyphs. In that scene there are humans and eagles but there is also a large humanoid figure standing next to a human looking figure. The carving resembles the big headed alien that people report seeing today and is shown as towering over the humans. Is that a possible sign that aliens visited the area many centuries ago?