The architectural appearance demonstrated by Flores Island was formed over centuries under the influence of the harsh Atlantic climate, isolation, and available natural resources. Unlike the opulent palaces of the mainland, restraint, functionality, and harmony with the volcanic landscape prevail here. Urban planning developed linearly along the coast, where the terrain allowed for the creation of safe harbours and settlements.
The island's main architectural milestones and styles can be divided into several key directions:
- Religious Architecture (Mannerism and Baroque). The most monumental structures on the island are Catholic temples. They are characterized by the "Azorean style": a contrast of whitewashed walls and dark basalt framing on corners, windows, and doorways.
- A striking example is the Church of Nossa Senhora da Conceição in Santa Cruz das Flores. Its majestic façade with two towers reflects the influence of Baroque, adapted to local capabilities.
- The former Franciscan Monastery of São Boaventura (now a museum) demonstrates the strict lines characteristic of Portuguese "plain architecture" (Arquitetura Chã) of the 17th century.
- Vernacular Architecture (Traditional Style). Traditional residential houses were built taking into account strong winds and humidity. These are squat rectangular buildings made of rough volcanic stone.
- Walls were often plastered and whitewashed, leaving the stone masonry exposed at the corners.
- Roofs were covered with red tiles, and chimneys had a specific shape resembling "hands," which became a hallmark of local ethnography.
- Impérios (Architecture of the Holy Spirit). Like all of Portugal, the island carefully preserves the traditions of the Holy Spirit festivals. This direction is characterized by small, brightly painted chapels — impérios. On Flores, they differ from their counterparts on other islands: they are stone structures on an elevation, often with an open-air altar or behind a grille, giving them a unique, almost theatrical appearance.
- Engineering and Lighthouse Architecture (19th–20th centuries). The development of navigation led to the appearance of iconic technical structures.
- Albarnaz Lighthouse on the northwestern tip of the island is a classic example of lighthouse architecture from the early 20th century. The cylindrical tower and the adjoining residential complex for keepers became a symbol of safety for transatlantic vessels.
- Functional Modernism (Mid-20th Century). The period of the French military base's presence brought elements of modern urbanism to the island. A residential quarter for personnel was built with standard concrete houses, wide streets, and developed infrastructure, which contrasted sharply with the chaotic development of old fishing villages. This district introduced new standards of comfort and planning.
Today, the island's urban development is strictly regulated by its Biosphere Reserve status. Modern buildings are required to blend into the landscape without disrupting the historical panorama, while ancient mills and whaling factories are reconstructed, transforming into cultural heritage sites.