The Page-Ladson site, currently buried and submerged in a sinkhole in northwestern Florida, demonstrates evidence of human occupation in North America by 14,550 calendar years ago (cal yr BP). This paper combines new diatom evidence with existing palynological data to strengthen paleoenvironmental interpretations at the site. The Page-Ladson sinkhole was not entirely submerged between ∼15,100 and 14,400 cal yr BP. Conditions at the site became warmer and wetter, and the sinkhole became a turbid pond from ∼14,400 to 12,900 cal yr BP. From ∼12,900 cal yr BP until ∼11,000 cal yr BP, a disappearance of diatoms in the coring location suggests the sinkhole margin was dry. Water levels rose between 11,000 and 9000 cal yr BP, submerging the coring location on the pond margin. These environmental data help contextualize the archaeological data in the region.