On August 11, 2006, an oil spill occurred in Panay Gulf when the oil tanker, MT Solar 1, sank off the coasts of Guimaras and Negros in the Philippines, causing what is considered to be the worst oil spill in the country's history.

Guimaras, officially the Province of Guimaras, is an island province in the Philippines located in the Western Visayas region. The capital is Jordan, while the largest local government unit for it is the municipality of Buenavista. The province is situated in Panay Gulf, between the islands of Panay and Negros. To the northwest is the province of Iloilo and to the southeast is Negros Occidental. The whole island is part of the Metro Iloilo–Guimaras, one of the twelve metropolitan areas of the Philippines.