While Sentosa is a natural island, its famous beaches—Siloso, Palawan, and Tanjong—are almost entirely man-made. These three stretches of coastline were created using reclaimed land and massive quantities of white sand imported primarily from Indonesia and Malaysia. The coastal area was originally rocky and jagged; the pristine lagoons and calm swimming areas seen today are the result of significant engineering, including the construction of artificial stone islets that act as breakwaters to prevent erosion. This development was part of Singapore's effort in the 1970s to transform the island (formerly known as Pulau Blakang Mati) from a military base into a world-class tourist destination. Even the palm trees were strategically planted to create a tropical aesthetic. Today, while the "nature" is carefully curated, the beaches serve as a massive recreational hub for millions of visitors seeking a resort-style escape within the city-state.