Lake Harris is part of a chain of lakes that comprise the Central Lakes region of the Central Lakes District. The county name, Lake, further attests to the predominance of the water-table lakes in this area. The district is characterized as sand hill karst with solution basins (Brooks and Merrit, 1981). In this area the Hawthorn Group pinches out onto the Ocala Limestone. Lake Harris has an irregular shape, covering 73 km² with about 62 km (38 mi) of shoreline. The lake narrows to Little Lake Harris to the south and Lake Denham to the west. Dead River joins the lake with Lake Eustis to the northeast. Sand hills with numerous small lakes within their interstices trend southeastward from the southern shore.