The Trinity River is a 710-mile-long (1,140 km) river that is the longest river that flows entirely within the U.S. state of Texas. It rises in extreme northern Texas, a few miles south of the Red River. The headwaters are separated by the high bluffs on the southern side of the Red River.
Robert Cavelier de La Salle, in 1687, called the stream the "River of Canoes". The name "Trinity" came three years later in 1690 from Alonso De León, who called the stream the "La Santísima Trinidad" ("the Most Holy Trinity").
Spring rains are collected in Fort Worth residential storm collection systems and flow down into Clear Fork of the Trinity River. The Trinity River travels Southward to near Galveston, Texas and is discharge into the Gulf of Mexico.
WikipediA Trinity River
Also see Spring Travel Part 2