from the shore) measurements. The island of Nusa Kambangan () sits on the south coast of Java and is separated from the main island by a narrow strait. It is a large and mostly uninhabited nature reserve, and is referred to as the Alcatraz of Indonesia, due to the three high security prisons that are located at the town of Permisan. Of all the measurements taken during the post-tsunami survey, the highest runup heights () were seen on the island behind a beach, where hibiscus and pandanus plants, and large coconut trees were mangled and uprooted up to from the shore. The (sea floor) bathymetry in the area supported a proposition that a canyon slope failure or an underwater landslide may have contributed to or focused the tsunami energy at that location. Nineteen farmers and one prisoner were killed there, but the deep water port of Cilacap (just to the east) was protected by the island, although one large moored vessel made ground contact during the initial withdrawal. Damage Since the earthquake caused only minor ground movement, and was only lightly felt, all the damage that occurred on the island was due to the tsunami. Types of buildings that were affected were timber/bamboo, brick traditional, and brick traditional with reinforced concrete. Semi-permanent timber or bamboo structures that were based on a wooden frame were the most economical style of construction that were assessed following the disaster. A tsunami flow depth of usually resulted in complete destruction of these types of structures. A group of scientists that evaluated the damage considered the unreinforced brick construction as weak, because the performance of homes constructed in that style did not fare much better than the timber/bamboo variety. Hotels and some houses and shops that were of reinforced brick construction were far better off, because units that were exposed to a flood depth of were considered repairable. Many wooden cafes and shops within of the shore were completely removed by the tsunami at Pangandaran, and severe damage still occurred to unreinforced masonry that was within several hundred meters, but some hotels that were constructed well held up better. The villages of Batu Hiu and Batu Kara, both to the west of Pangandaran, experienced similar damage. Other severe damage was seen at Marsawah village, Bulakbenda, where all buildings had been removed down to their foundation within of the water line, and even further inland there