Castalian Springs is an unincorporated community and census-designated place (CDP) in Sumner County, Tennessee, United States. It is located along Tennessee State Route 25, about seven miles east of Gallatin. The area has its own United States post office, designated by the Zip code 37031. In the early 19th century, it was known locally as Bledsoe's Lick, and was the location of Bledsoe's Station, a fortified trading post. As of the 2010 census, its population was 556.
In the 2008 Super Tuesday tornado outbreak of February 5–6, the tiny village was hit by a strong tornado (at least EF2) that claimed seven lives. The historic structure Wynnewood was heavily damaged by the storm and the United States post office was destroyed. Castalian Springs captured national news headlines when an 11-month-old boy, Kyson Stowell, was found alive in the debris of his house. Originally thought to be a children's doll, the boy moved just slightly and rescuer, David Harmon, noticed the movement. He had been blown 150 yards from the house. Kyson's mother had shielded him but died in the storm.