| Lake Ontelaunee | |
|---|---|
 Lake Ontelaunee, November 2007 | |
  Lake Ontelaunee  Lake Ontelaunee | |
| Location | Berks County, Pennsylvania |
| Coordinates | 40°27′44″N 75°55′17″W / 40.4622°N 75.9214°W |
| Type | reservoir |
| Basin countries | United States |
| Surface area | 1,082 acres (438 ha) |
Lake Ontelaunee is a 1,082-acre (4.38 km2) reservoir that is located in Berks County, Pennsylvania. Blue Marsh Lake, another artificial reservoir, is the largest lake in Berks County, making Lake Ontelaunee the second-largest lake.