Early Filipinos had a writing system and recorded places in Bulacan and Tondo. The Laguna Copperplate Inscription, dated to 900 AD, is the earliest known calendar dated document found in the Philippines. Early Filipinos engaged in farming, shipbuilding, mining, weaving and had knowledge of martial arts and weaponry. During the Spanish colonial period, infrastructure like government buildings, churches, roads and bridges were constructed, such as the Malagonlong Bridge in Tayabas, Quezon and the Paoay Church in Ilocos Norte.