Karimun Besar is the main island of Karimun Regency in Indonesia's Riau Islands. The visitor hub is Tanjung Balai Karimun, a port town on stilts at the south end of the island, about 37 kilometres southwest of Singapore. Wonderful Indonesia places the island with Batam and Bintan in the Batam-Bintan-Karimun Free Trade Zone. This guide is the island overnight stop: Pelawan, Ketam and Pongkar beaches, Mount Jantan, and the Pongkar waterfall. It is not a Batam or Bintan resort guide. It is not Tanjung Balai Asahan in North Sumatra.
One night is enough for the harbour town plus one beach or the waterfall loop. Two nights fit if you want a slow seafood evening and a second coast. A week has nowhere to spend it unless you treat the island as a work stop. Do not invent a second dining strip under the palms; eat where the town already cooks. BPS-linked estimates put about 156,419 people on Great Karimun and adjacent small islands in mid-2024. The wider regency census was 253,457 in 2020, with a mid-2025 estimate of 276,650. Do not mix those headcounts.
There is no useful visitor airport hop from Singapore. Sindo Ferry publishes HarbourFront sailings to Tanjung Balai at 11:40 and 18:20, and returns from Tanjung Balai at 07:30 and 14:00 Western Indonesia Time. The crossing is about one and a half hours on the national tourism page. Confirm the operator sheet the week you travel; slots move. Two terminals sit in Tanjung Balai: the international one toward Singapore, Batam, Bintan and Malaysia, and a local berth about 500 metres toward the centre for Kundur and nearby islands.
A strait island, not the Asahan namesake
Portuguese reports in the sixteenth century already treated the island as inhabited, possibly by Orang Laut. In the eighteenth and nineteenth centuries it sat under the Johor Sultanate and later the Riau-Lingga Sultanate. Dutch agents inspected the northwest coast around 1615 for a fort that was never built. William Farquhar surveyed it later and found rocky ground and a thin fresh-water case, so the British trading post went elsewhere.
Today the island is the crowded core of Karimun Regency. Wonderful Indonesia calls Tanjung Balai a medium town largely on stilts, with a Chinese Peranakan strand and temples; the oldest named on that page is Vihara Cetiya Vidya Sagara, built in 1926. Landmarks on the island sheet include Mount Jantan, Pelawan, Ketam and Pongkar beaches, and the Pongkar waterfall. Indonesia Travel also writes Palawan for the same west-side beach cluster; keep one spelling and do not invent a second beach.
