Mostyn is on the Burlington-Rock Island Railroad at the junction of Farm roads 1488 and 149, three miles east of Magnolia and fourteen miles west southwest of Conroe in southwestern Montgomery County. In 1906 or 1907 the Trinity and Brazos Valley Railway built a line through the area. A post office was established in Mostyn in 1908 but was discontinued in 1918. By 1915 the town had a population of fifty; a sawmill was owned by G. J. Sunday, and K. P. Edwards was postmaster and storekeeper. By 1946 the railroad had been purchased by the Burlington-Rock Island Railroad, and Mostyn had one business and several scattered dwellings. In 1962 the railroad line was part of the Fort Worth and Denver Railway, and Mostyn had twenty-five scattered dwellings and a Baptist church. In 1979 there were three churches and a business located near the railroad depot. In 1990 the town had a few houses at the crossroads, the St. Matthew's Baptist Church, and a restaurant.