Tirad Pass in Gregorio del Pilar, Ilocos Sur is one of the most historically significant hiking destinations in the Philippines — site of the Battle of Tirad Pass in 1899 during the Philippine-American War where General Gregorio del Pilar sacrificed himself and his men to protect the retreat of General Emilio Aguinaldo. The hike to the pass combines natural mountain scenery with one of the most moving chapters of Philippine history.