Guaranto Spring, also locally known as “Gronto” or “Gornto” Spring, is an impounded swimming hole along the west side of the Suwannee River. An earthen dam blocks the outflow channel adjacent to the river, creating an oblong spring pool. The pool measures 240 ft (73.2 m) northwest to southeast and 87 ft (26.5 m) northeast to southwest. The depth over the vent is 11.5 ft (3.5 m). A slight boil is present on the northwest end of the pool directly over the vent. The water is clear and greenish. The spring has a sand bottom. Limestone is exposed at the vent. Algae are abundant, but there is virtually no aquatic vegetation. Two wooden access structures are built into the pool on the north and south sides. The north shore has bluish clay banks, and the spring’s steep banks rise to approximately 12 ft (3.7 m) above the water level. The land around the spring is developed into a county recreation park. The spring discharges through a 5 ft (1.5 m) diameter culvert in the dam directly into the Suwannee River.
Guaranto Spring is located within a county park along the west bank of the Suwannee River, 12.5 miles (20 km) south of Branford. Travel west from the Suwannee River bridge in Branford on US 27 for 1.3 miles (2.1 km). Turn south (left) on SR 349 and travel 11.8 miles (19 km). Turn east (left) on CR 353 (Rock Sink Church Road) at the flashing lights. The road turns sharply to the south (right) just in front of the church, follow the road approximately 2.5 miles (4 km) to the county park.