1. Madapollu
This artificial island is located off the coast of Visakhapatnam in Andhra Pradesh, India, and serves as a marine sanctuary. Spanning approximately 3.2 million square feet (295,000 square meters), it is home to a wide variety of marine life, including coral reefs and sea fans. The island features several artificial reefs, helping to support the biodiversity of the region. Madapollu was created in 1986 by dumping sediment from dredged materials.
2. Palau's Rock Islands
Comprising over 300 tiny islands, the Rock Islands are a stunning example of artificial landscape engineering. Stretching approximately 80 miles (130 kilometers) along the western coast of the Pacific island nation Palau. This archipelago consists mainly of limestone and coral formations, rising dramatically from the turquoise waters. The Rock Islands were formed through millions of years of geological erosion.
3. Zanzibar's Jozani Chwaka Bay
Located off the southeastern coast of Tanzania's Zanzibar Archipelago lies this artificial island, also known as Jozani. Spanning approximately 20 acres (8 hectares), it features lush tropical forests and mangrove swamps. Jozani Chwaka Bay is a natural sanctuary and one of Tanzania’s most pristine wildlife areas, where the rare red colobus monkey can be found. The bay itself was formed in the early 1990s as part of conservation efforts.
4. The Isles of St. Kilda
Comprising two primary islands and numerous smaller rocks, this archipelago is situated about 35 miles (56 kilometers) west off the north coast of Scotland's mainland. Established in 1931 as a British nature reserve due to its exceptional status for seabird populations and their habitats, it now includes 18 islands covering an area of approximately 27 km² (10.4 sq mi). The islands were artificially created through volcanic activity thousands of years ago.
5. Bonaire's Sonneveld Rock
A notable artificial reef off the coast of Bonaire in the southern Caribbean, lies this famous rock formation at about 2 miles from shore. Created by natural erosion and human influence alike to support marine diversity and biodiversity. Measuring approximately 1 mile (1.6 kilometers) along its coastline, it features a submerged cave system that also protects fish larvae and plankton communities.