The Adams County Travel and Visitor Bureau (ACTVB) has a wonderful website which you should visit. Included on their site are addresses of historical sites, and a delightful photo slideshow of photos by Tom Cross, showing historical sites, local scenery, projects and events in Adams County. You can find their website at: http://www.adamscountytravel.org.
The Great Serpent Mound is a 1,330-foot-long, three-foot-high prehistoric effigy mound located on a plateau of the Serpent Mound crater along Ohio Brush Creek in Adams County, Ohio. Maintained within a park by the Ohio Historical Society, it has been designated a National Historic Landmark by the United States Department of Interior. The SerpentMound of Ohio was first reported from surveys by Ephraim Squire and Edwin Davis in their historic volume Ancient Monuments of the Mississippi Valley published in 1848 by the newly founded Smithsonian Museum. The head of the serpent is aligned to the summer solstice sunset and it is thought that the coils may also point to the winter solstice sunrise and the equinox sunrise.
A public park for more than a century, Serpent Mound attracts visitors from all over the world. The museum contains exhibits on the effigy mound and the geology of the surrounding area. http://ohsweb.ohiohistory.org
A reprint of a 1907 book called, "Serpent Mound, Adams County, Ohio" can be found on Google Books. It can be read online for free, but is copyrighted so it cannot be downloaded.
Links to Other Interesting Websites
Adams County Travel and Visitors Bureau - Local Historical Sites, complete with descriptions, directions, and maps.
Do you have some links that you think will be helpful to researchers? If so, please send them to me and I'll check them out. If I think they should go here, I'll put them up. Send them to: firstname.lastname@example.org. Please remember to put "Adams County" in the subject line.