The Historic Town of Vigan was inscribed on the basis of the following:
Criterion (ii): exhibit an important interchange of human values, over a span of time or within a cultural area of the world, on developments in architecture or technology monumental arts or town planning and landscape design.
Under this criterion, the World Heritage Center officially cites: "Vigan represents a unique fusion of Asian building design and construction with European colonial architecture and planning.
Criterion (iv): "be an outstanding example of a type of building or architectural or technological ensemble or landscape which illustrates a significant change in human history.
Under this criterion, the citation reads: "Vigan is an exceptionally intact and well preserved example of a European trading town in East and East Asia.
To understand better these citations, let us explore together the town planning, the evolution and typical layout of the Vigan House.
TOWN PLANNING
Strategically located at the mouth of the Abra River along the northwestern coast of Luzon which is nearest to mainland China, Vigan was an important coastal trading port from the pre-colonial era to the 19th century. The town plan is representative of the style the Spanish colonizers had designed and established in the 18th century, conforming to the Ley de las Indias (the Law of the Indies) that regulated the lay-out, street patterns and open spaces of all new settlements during the Spanish era: a regular urban design of grid street pattern radiating from a central plaza (park).