Peoria Heights is a village lying almost entirely in Peoria County in the U.S. state of Illinois. The population was 6,156 at the 2010 census, down from 6,635 in 2000. Peoria Heights is a suburb of Peoria and is surrounded by the city except for its eastern boundary on Peoria Lake, a relatively wider section of the Illinois River. It is part of the Peoria, Illinois Metropolitan Statistical Area. According to the 2010 census, Peoria Heights has a total area of 6.969 square miles (18.05 km2), of which 2.65 square miles (6.86 km2) (or 38.03%) is land and 4.319 square miles (11.19 km2) (or 61.97%) is water. That most of the village is water is due to the fact that most of Upper Peoria Lake lies within its boundaries; this can be seen on official state maps.
Topographically, the village can be roughly divided into three zones. The Illinois River floodplain, the bluff, and the plateau. While its eastern border is fairly regular with the river’s edge, the rest of its municipal border, with Peoria, is quite irregular and convoluted.According to the Census Bureau records through 2007, Peoria Heights lies in three counties (Peoria, Woodford, and Tazewell). While neither Tazewell nor Woodford counties consider Peoria Heights to be within their jurisdiction, the state of Illinois does show that across Peoria Lake from the rest of the village, a small, uninhabited area exists both within Peoria Heights and Woodford County.
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