The nearly  road has major intersections with RM 1174 and  US 183 at its termini and has short concurrencies with  SH 29 and again with RM 1174 in Bertram. RM 243 passes through a portion of a national wildlife refuge and crosses two forks of the San Gabriel River.
The nearly  road has substantial connections with RM 1174 and US 183 at its ends, as well as brief overlaps with SH 29 and once more with RM 1174 in Bertram. RM 243 passes through a portion of a national wildlife sanctuary and crosses two forks of the San Gabriel River.