Wasini Island is located off the coast of southeast Kenya in the Indian Ocean. It sits approximately 75 kilometres (47 mi) south of Mombasa and is positioned 3 kilometres (1.9 mi) opposite the harbour of the village of Shimoni. The island measures roughly 7 kilometres (4.3 mi) in length and 3 kilometres (1.9 mi) in width.
The island is characterized by its lack of motorized vehicles, including cars, carts, or bicycles. Transportation across the land consists of footpaths made of sand or sharp old coral, while cargo is moved by foot or via wheelbarrows with solid tyres. Travel over the beaches is only possible during low tide due to the coral composition. Historically, a small tarmac airstrip existed in the lagoon south of the island during the British colonial period before 1963.