Outer Islands | Seychelles

The Outer Islands (Les Îles Éloignées) of the Seychelles consist of 72 coral islands and atolls situated between 230 km and 1,150 km south and southwest of Mahé. Unlike the granitic Inner Islands, these are low-lying coral formations with a total land area of approximately 211 $km^2$, but they are spread across a vast maritime zone of 1.1 million $km^2$.

Structural Groups

The Outer Islands are divided into five distinct geographical groups:

Amirantes Group: Located closest to the Inner Islands; includes Desroches, D'Arros, and Poivre.

Alphonse Group: Comprising Alphonse Atoll and St. François Atoll; famous for fly-fishing.

Southern Coral Group: Includes Platte and Coëtivy islands; known for salt and shrimp production.

Farquhar Group: Situated in the far south; includes Farquhar Atoll and Providence Atoll.

Aldabra Group: The most remote group; includes the Aldabra Atoll, Assumption, Cosmoledo, and Astove.

Historical Timeline

9th–15th Century: Likely visited by Arab and Maldivian seafarers, but remained unsettled.

1502: Vasco da Gama sighted the Amirantes during his second voyage to India.

1965: Several islands (Aldabra, Farquhar, Desroches) were detached to form the British Indian Ocean Territory (BIOT).

1976: Returned to the Seychelles upon independence.

1982: Aldabra Atoll designated a UNESCO World Heritage site.

Key Islands & Atolls

Aldabra Atoll: The world’s second-largest coral atoll. It is an "Evolutionary Fortress" home to over 150,000 Aldabra giant tortoises-the largest population on Earth.

Desroches Island: The largest island in the Amirantes. It hosts a luxury Four Seasons resort and a significant coconut plantation.

Alphonse Island: A premier destination for world-class salt-water fly-fishing, particularly for bonefish and giant trevally.

Assumption Island: Primarily used as a transit point for Aldabra; known for its 1,200m airstrip and historical guano mining.

Coëtivy Island: Known for its large-scale aquaculture, specifically black tiger prawns.

Ecology & Conservation

The Outer Islands are managed primarily by the Islands Development Company (IDC) and the Seychelles Islands Foundation (SIF).

Marine Biodiversity: These waters contain some of the most pristine coral reefs in the Indian Ocean, serving as critical spawning grounds for tuna and billfish.

Birdlife: Major nesting sites for millions of sooty terns, frigatebirds, and the flightless Aldabra Rail (the last flightless bird in the Indian Ocean).

Turtle Nesting: One of the world’s most important regions for Green and Hawksbill sea turtles.

Transportation & Logistics

Air: Accessible via IDC charter flights from Mahé. Flight times range from 40 minutes (Desroches) to over 3 hours (Assumption/Aldabra).

Sea: Reachable via private yacht or IDC supply vessels. Transit to Aldabra by sea can take 2–3 days from Victoria.

Permits: Most Outer Islands require prior authorization from the IDC or SIF to land. Unauthorized landing is strictly prohibited for conservation reasons.

Safety & Infrastructure

Isolation: There are no public hospitals or commercial infrastructure. Emergency medical evacuation is extremely difficult and expensive.

Piracy: While the threat has significantly decreased since 2013, the Seychelles Coast Guard still patrols these waters to prevent illegal fishing and maritime crime.

Climate: Highly susceptible to cyclones, particularly the Farquhar and Aldabra groups (unlike the Inner Islands which are outside the cyclone belt).

Digital & Financial Infrastructure

There is no public mobile network on most Outer Islands. Communication is via satellite phone or limited VSAT internet at research stations and luxury resorts. There are no ATMs; all transactions are pre-arranged or handled at the resorts.

Local Cost Index

1 Charter Flight (Mahé to Alphonse): ~€600 – €900 ($650 – $980)

1 Day Entry Fee (Aldabra): ~€200 ($220)

1 Night (Luxury Resort): ~€1,500 – €3,000 ($1,630 – $3,260)

Facts & Legends

A verified biological fact is that the Aldabra Atoll is one of the few places on Earth where a reptile-the giant tortoise-is the dominant herbivore, filling the ecological niche occupied by mammals elsewhere. Local legend among Seychellois sailors tells of "The Phantom Atoll" in the Farquhar group, which is said to disappear beneath the waves during high tide, trapping unwary treasure hunters who seek 18th-century pirate caches.