Summer or swing beam, Oak, from a barn(s) in Ohio, re-purpose project. 12" thick. Close to 2' tall in the center. Gunstock posts in the background were similar size @ the top.
The first bent we picked weighed 2700#s if I remember correctly. 2 posts, 2 braces, that summer beam.
Yeah, I've wondered and marveled at the things folks have done with out cranes and power tools...