DeLand Hall — 1884
DeLand Hall, erected in 1884, became the first building in Florida continuously used for higher education [S19].

Quick answer: Stetson University in DeLand, Florida is the oldest private college in the state. It was founded by Henry A. DeLand as DeLand Academy on November 5, 1883, and renamed John B. Stetson University in 1889. DeLand Hall, built 1884, is the first building in Florida continuously used for higher education.
In the First Baptist Church of DeLand's lecture room on November 5, 1883, Henry A. DeLand and Dr. John H. Griffith inaugurated DeLand Academy [S20].
In 1884, DeLand Hall was built — now the first building in Florida continuously used for higher education [S19].
The institution was incorporated as DeLand University in 1887 and renamed John B. Stetson University in 1889 to honor the hat-maker whose philanthropy kept it solvent [S19, S20].
DeLand Hall, erected in 1884, became the first building in Florida continuously used for higher education [S19].
The university campus comprises the Stetson University Historic Campus District, featured on walking tours by the West Volusia Historical Society and Walking DeLand Tours [S38, S39].
Stetson Campus walking tour