Palaui Island lies off the northwestern part of a large promontory in San Vicente, in the municipality of Santa Ana, Cagayan province. It is 10 kilometres (6. 2 mi) at its longest and about 5 kilometres (3. 1 mi) at its widest and moderately high. The western shore of the island appears bold, but on the eastern side, a reef projects from its side for 2. 4 kilometres (1. 5 mi), the edge of it being 0. 8 kilometres (0. 50 mi) from and extending around the small islet of Escucha, east of Palaui. The Dos Hermanos rocky islets lie off Cape Engaño, in the northern point of Palaui, and there are some rocks off the northeast point of the island, about 1. 6 kilometres (0. 99 mi) eastward of the cape. Gran Laja island, a low rock islet surrounded by breakers, is one of the rocks located northeast off Palaui.