Trenton is located at 39Â°28â²55â³N 84Â°27â²34â³Wï»¿ / ï»¿39.48194Â°N 84.45944Â°Wï»¿ / 39.48194; -84.45944 (39.481909, -84.459460). The city lies on the west bank of the Great Miami River. According to the United States Census Bureau, the city has a total area of 4.56 square miles (11.81 km 2), all land.