Maps mark an expanding shore

A large-scale map from 1889 shows Ilha Verde as an island northwest of the Macao Peninsula. Maps made less than a decade later show a narrow causeway connecting it to the peninsula. Together, the 1889 map and the 1922 harbour plan show how Ilha Verde’s separation from the city and the outline of the Outer Harbour changed over time.

A different map from 1922, the plan for works on an artificial harbour, shows schemes for reclamation that would not all be completed for decades. The plan anticipated parts of later projects, including the Outer Harbour and Nam Van Lake. It is a planning document, not a photograph of what had already been built; its value lies in showing how future shorelines were imagined.

Macao’s land area was first measured at 11.6 square kilometres in 1912. The 2024 Macao Yearbook records 33.3 square kilometres in 2023, with the Cotai Reclamation Area listed at 6.1 square kilometres, or 18.3 percent of the total. These figures describe land area at two dates, not the length of the shore.

A separate coastline map based on a survey dated 1 May 2025 measures 79.5 kilometres. It divides that total among the peninsula, outlying islands including Taipa, Cotai and Coloane, and new urban zones. Area and coastline answer different questions: how much land is counted, and how much boundary meets the water.

The 1889 map, the 1922 harbour plan, the 1912 land-area figure, the 2023 yearbook and the 2025 coastline survey form a dated series of records. Each uses a different representation: a surveyed map, a proposed engineering plan, a statistical measurement or a modern boundary survey. Read together, they document the scale and chronology of shoreline change without pretending to be the same kind of evidence.

The maps alone do not establish the ecological effect of every reclamation project. That question requires habitat and monitoring data from particular places and periods. What the dated records do show is a large expansion in mapped land area and a coastline now measured across the peninsula, islands, reclamation areas and new urban zones.