Olla is a Town in northwest La Salle Parish, Louisiana, United States, located in the heart of the Louisiana Central Hill Country.Olla has a federally recognized downtown Historic District and a Louisiana historic marker. The population was 1,617 at the 2010 census. Olla Historic District is the site of the annual Central Louisiana Bluegrass Festival each April and to the Olla Homecoming Parade, Celebration, and Festival that coincides with LaSalle High School Homecoming each autumn.The Town of Olla also hosts an annual nighttime Christmas Parade, Miss Merry Christmas Pageant, and Community Christmas. These events occur on the Friday locals schools release for Christmas break. The parade begins at the Olla Elementary School and terminates at Santa's Gazebo in the Olla Town Square. The Olla Town Square in located within the Olla Historic District and contains the Olla Farmers Market/Community Pavilion, Wishing Tree, Dixie Center, Gazebo, historic marker, and a stage.