Tongatapu is the largest island in the Kingdom of Tonga. It is home to two thirds of its people. A roughly triangular shaped island measures about 34 km across from west to east. Most of the island is less than 17 meters above sea level. The capital Nukualofa, is a slow paced city of about 30,000 inhabitants.
The archeological site of Haamonga is very impressive and should not be missed. Mua is a good place from where to see it.

The island is an area of raised reef limestone on a deep base of volcanic sedimentary rock. The low northern cost is a reef platform, in places up to 200 meters in width. The high windward side of the eastern coast is known as lilu has a narrow reef ledge varying in height from 6 to 46 meters. The highest point of 65 meters lays between the airport village of Fu’amotu and Nakolo.

The south and east coasts face very deep water. See the blowholes at Houma. Here waves crash against the reef and through blowholes create spectacular sights. From south east coast the island of Eua is visible. Tongatapu has no rivers are streams. Tongatapu’s drinking water supply come from underground, called the water lens. Rainwater falling on the islands permutes and floats on top of the heavier sea water. This water is pumped up for the town supply. Rainwater collected in tanks is an alternative source of drinking water for many a Tongan home.