A sliver of old Singapura survives at the eastern end of West Coast Park off a now largely sandless Pasir Panjang. Here, the survivors of an extinct archipelago gather their wits and wounds to claim a tiny fraction of the space they once roamed, a weekend refuge from which they can launch their bodies from the confines of the mainland into channels, reefs, fairways and shoals that are mapped into their minds and forever buried in their hearts.