Palmyra is an unincorporated community in Montgomery County, Tennessee. It is located along State Route 149, southwest of Clarksville. The town had its own post office until around 2010 when the post office was closed and mail service began to be handled out of nearby Clarksville. The zip code for Palmyra is 37142. Palmyra was laid out by Morgan Brown and established by the legislature in 1796.