Kalpeni's geography is entirely defined by its relationship to the surrounding waters.
* **The Lagoon:** A vast, shallow, and brilliantly turquoise lagoon separates the main island from its satellite islets. It serves as the primary waterway for local navigation, fishing, and recreation. * **Arabian Sea:** The atoll is surrounded by the deep waters of the Arabian Sea, which functions as the main maritime route for deep-sea fishing vessels and passenger ships arriving from the mainland.