The island is densely wooded and rises to a height of 227m in its central part.
Katchall Island has been reported to be a good radar target up to 18 miles.
Depths off the W side of the island are very irregular. Some 16.5 to 18.3m patches lie up to 4 miles off this coast.
On 26 December 2004, several islands were heavely damaged by the Tsunami.