Ranch to Market Road 243

RM 243 was originally designated on June 11, 1945, as Farm to Market Road 243 (FM 243), a 13.8-mile (22.2 km) from SH 29 in Bertram to a location TxDOT identifies as Green's Corner at the road's eastern terminus on what was then SH 74.[1] On July 14, 1949, the road was extended 5.7 miles (9.2 km) to Oatmeal.[1] US 183 was rerouted eastward south of Albany along a new route that includes the present section between Briggs and Austin at the Green's Corner terminus.[1][2] On October 31, 1957, RM 243 received its current Ranch to Market designation and was extended 2.6 miles (4.2 km) to RM 1174,[1] which was extended southward from Bertram at the same time.[3]

RM 243 begins at RM 1174 in Balcones Canyonlands National Wildlife Refuge in Burnet County.[4] The road proceeds northward passing through Oatmeal before crossing the South Fork of the San Gabriel River, then turns to the northeast toward Bertram.[5] In Bertram, RM 243 joins SH 29 to the southeast until turning back to the northeast along N. Grave St. joining RM 1174.[6] On the north edge of town, RM 1174 separates to the north, then RM 243 leaves town to the northeast and crosses the North Fork of the San Gabriel River.[5][7] The road then passes through Mahomet before it terminates immediately after crossing into Williamson County at US 183 between Liberty Hill and Biggs.[7]