Aroostook County ( French : Comté d'Aroostook ) ( / ə ˈ r uː s t ə k / ə- ROOS -tək ) is a county in the U.S. state of Maine along the Canada–U.S. border . As of the 2010 census , the population was 71,870.  Its seat is Houlton . 
Presque Isle / p r ɛ s k aɪ l / is the commercial center and largest city in Aroostook County , Maine , United States. The population was 9,171 in 2015 as estimated by the US Census, a decrease from the count of 9,692 in the 2010 Census .  The city is home to the University of Maine at Presque Isle , Northern Maine Community College , Husson University Presque Isle,  Northern Maine Fairgrounds, The Aroostook Centre Mall , and the Northern Maine Regional Airport .