A. O. Smoot told W. Woodruff that He & Alanson Ripley while surveying out Adam Ondi Ahman about 22 Miles North of Jackson County Missouri they Came across a Stone wall in the midst of a dens forest & underbrush. The wall was 30 feet long 3 feet thick, and about 4 feet high above the ground and laid in mortar or Cement. When Joseph Smith the Prophet visited the place and Examined the wall He said it was the remains of an Altar Built By Father Adam whare he offered Sacrafice after he was driven from the Garden of Eden which was located in Jackson County Missouri. The whole town which was laid out and named Adam Ondi Ahman was in the midst of a thick & heavy forest of timber and the place named after Adams Altar. The Prophet Joseph said it was upon this Altar whare Adam blessed his sons and Posterity Before his death. Let Historians of the Church note this.
[Source: Wilford Woodruff's Journal: 1833-1898 Typescript, Volumes 1-9, Edited by Scott G. Kenney, Signature Books 1993, http://amzn.to/newmormonstudies]