Tres Palacios, also known as Tidehaven, was a port community on the Tres Palacios River south of Hawley and near what is now Farm Road 459, thirteen miles southwest of Bay City in western Matagorda County. Pumphrey Burnett was reportedly the founder of Tidehaven, so named because it was just beyond the farthest reach of the invading tidewaters of Palacios Bay. A local history reports that during the 1830s and 1840s steamers regularly stopped at Tidehaven, which at one time had a blacksmith shop, a grocery store, a livery stable, and two hotels. Shipments through Tres Palacios included cotton, peaches, sugarcane, cattle, and hides, which may have been tanned at the nearby Grimes Ranch tannery. A meat cannery also operated in the vicinity. The community name was changed to Tres Palacios with the March 1856 establishment of the Tres Palacios post office. Though the post office was closed by July of that same year, it was reestablished in 1888. It closed again temporarily in 1903, and then permanently in 1904, when local mail was routed through Blessing. By at least 1857, Methodist circuit riders were preaching at Tres Palacios. The 1870 census enumerated around 275 people living at Tres Palacios and nearby Wilson's Creek. By 1892 the community had a flour mill and gin, in addition to a general store, and by 1896 a daily mail stage to El Campo served its population of seventy-five. During the 1894 election to determine the next county seat, Tres Palacios was one of six county voting precincts and overwhelmingly chose Bay City over Matagorda. A school existed at Tres Palacios sometime before 1890, and by 1894 it served at least nine students. In 1904 it had eight White students. Though in 1909 the St. Louis, Brownsville and Mexico Railway had a stop called Tres Palacios or Tidehaven, the town appears to have dwindled away by the mid-1930s, as the 1936 county highway map does not show it. Its original name lives on in Tidehaven Independent School District and the district's Tidehaven High School, which is located only a few miles east of the port community's original site.