Ilopango is a large volcanic lake located in El Salvador. It was formed by a massive eruption around 2,000 years ago, which created a caldera. The lake is known for its stunning blue waters and is a popular destination for both locals and tourists. The surrounding area features lush vegetation and diverse wildlife, making it an attractive spot for outdoor activities like hiking and birdwatching. Ilopango is also significant for its historical and cultural importance, as it has been a vital resource for the communities nearby.