On August 1, 1973 President Ferdinand E. Marcos issued Proclamation No. 260. It is the presidential decree that declared, among others, the Site of the Battle of Mactan on Mactan Island, Cebu and the Church and Convent of Santo Niño in Cebu City as national shrines, monuments, and/or landmarks.
In the decree, the law invokes the provision of the Constitution that "Filipino culture shall be preserved and developed for national identity." A national law, Republic Act 4846 declares that it is the policy of the State to preserve and protect the cultural properties of the nation."
The issuance of the decree was done by virtue of the powers vested in the president by the Constitution as commander-in-chief of all the Armed Forces of the Philippines, and pursuant to Proclamation No. 1081 dated September 21, 1972 and General Order No. 1 dated September 22, 1972 which simply means that the nation was under Martial Law.
Under the decree, the law allocated the amount of P500,000 to carry out the intents of the decree, it was given to the National Historical Commission from the National Treasury.
The decree also empowered the National Museum and the National Historical Commission with the right to declare other such historical and cultural sites as national Shrines, monuments, and/or landmarks in accordance with the guidelines set for in Republic Act 4846.
Aside from the Site of the Battle of Mactan, Mactan Island, Cebu and the church and convent of the Santo Niño in Cebu City, the presidential decree also declared the following as national shrines, monuments and landmarks: Sta. Ana Site Museum in Manila, the Roman Catholic churches of Paoay and Bacarra in Ilocos Norte, the San Agustin Church and liturgical objects therein in Intramuros, Manila, Fort Pilar in Zamboanga City, the Petroglyphs of the Rockshelter in Angono, Rizal, the Petroglyphs of Alab, Bontoc, the Stone Agricultural Calendars of Dap-ay Guiday in Besao, Bontoc, the Mummy Caves of Kabayan, Benguet and Segard and Alab, Bontoc, the Ifugao Rice Terraces of Banaue were also declared as National Cultural Treasures. Its preservation, restoration and/or reconstruction were made under the supervision and control of the National Museum in collaboration with the Department of Tourism.
The decree also mandated that the Barasoain Church in Malolos, Bulacan, Tirad Pass in Cervantes, Ilocos Sur, the Miagao Church in Miagao, Iloilo, the Site of the Battle of Mactan Island in Cebu , the San Sebastian Church in Quiapo, Manila and the Church and Convent of Sto. Niño in Cebu City be declared as national shrines and its preservation, restoration and/or reconstruction made under the supervision and control of the National Historical Commission in collaboration with the Department of Tourism.
It was also President Marcos who declared every April 27 as "Battle of Mactan" and April 28 as a Special Public Holiday in Lapu-Lapu City and Cebu Province. This was contained under Presidential Proclamation No. 1845, issued on April 19, 1979.
The proclamation was issued on the 458th year marking the Battle of Mactan which produced the country's first national hero, Lapu-Lapu. Incidentaly, April 27 also marks the anniversary of the promulgation of the Charter of Lapu-Lapu City, Cebu.
The Presidential Decree explains that the residents of Lapu-Lapu City desired to celebrate the milestone of their city and that the event signified the historical evolution of the whole Province of Cebu.