Ilocos Sur

Ilocos Sur, officially the Province of Ilocos Sur,  is a province in the Philippines located in the Ilocos Region in Luzon. At the mouth of the Mestizo River is the capital, Vigan. Ilocos Sur is next to Ilocos Norte and Abra to the north, Mountain Province to the east, La Union and Benguet to the south and the South China Sea to the west.

Ilocos Sur was founded by the Spanish conquistador Juan de Salcedo in 1572. It was formed when the north (now Ilocos Norte) split from the south (Ilocos Sur). At that time it included parts of Abra and the upper half of present-day La Unión. The current boundary of the province was permanently defined through Act 2683 signed in March 1917.

The province is home to two UNESCO World Heritage Sites, the Heritage City of Vigan and the Baroque Church of Santa Maria.