Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Oberentfelden is a municipality in the district of Aarau of the canton of Aargau in Switzerland. Oberentfelden has an area, as of 2006[update], of 7.2 square kilometers (2.8 sq mi). Of this area, 29.4% is used for agricultural purposes, while 42.3% is forested. Of the rest of the land, 28% is settled (buildings or roads) and the remainder (0.3%) is non-productive (rivers or lakes). The municipality is located in the Aarau district in the lower Suhr valley. The villages of Oberentfelden and Unterentfelden, while distinct municipalities, have grown together.