Transportation between the three islands of Grande Comore, Mohéli, and Anjouan relies on irregular boat services and limited air connections. AB Aviation operates inter-island flights, though schedules change frequently and cancellations occur without advance notice. The boat crossing from Moroni to Anjouan takes approximately six to eight hours depending on sea conditions in the Mozambique Channel, with departures clustered around Friday for weekend returns. Mohéli Marine Park authorities operate occasional charters between Mohéli and Grande Comore, but these serve researchers and conservation staff primarily. No published ferry timetable exists that tourists can reliably reference months in advance.
On Grande Comore, taxi-brousses follow the coastal ring road connecting Moroni to Mitsamiouli in the north. These shared minivans depart when full, typically seating twelve to fifteen passengers. The route from Moroni to the Mount Karthala trailhead requires arranging private transport, as public vehicles do not service the interior volcanic slopes. Motorcycle taxis operate in Moroni and Mutsamudu but helmet availability is inconsistent. The coastal road on Grande Comore is paved for most of its approximately 75-kilometer length, though sections near Iconi deteriorate during the November-to-April rainy season.
Anjouan's road network connects Mutsamudu to Domoni along the northern coast, with a partially paved route crossing the interior to Ouani. Taxi-brousses on Anjouan are smaller than Grande Comore equivalents, often seating eight passengers. The drive from Mutsamudu to Domoni takes roughly one hour under dry conditions. Mohéli has approximately 30 kilometers of navigable roads, mostly concentrated around Fomboni. Transportation on Mohéli typically requires pre-arrangement with guesthouses, as taxi-brousse services are intermittent outside the capital.
Car rental exists only in Moroni, where two agencies offer vehicles at rates starting near 35,000 KMF per day without insurance. International driving permits are required alongside a national license, though enforcement varies. Fuel stations operate in Moroni, Mutsamudu, and Fomboni, with unleaded petrol priced around 1,100 KMF per liter as of 2023. Grande Comore has additional stations in Mitsamiouli and Iconi. Fuel shortages occur periodically on all three islands, sometimes lasting several days.
Walking remains the primary transport method within Moroni's medina and the old town areas of Domoni and Mutsamudu. The medina of Moroni covers less than one square kilometer, navigable on foot in under twenty minutes. Mitsamiouli to Moya Beach is approximately three kilometers along the coastal road, walkable but exposed to sun with limited shade. Trails on Mount Karthala require guides, arranged through the Direction Nationale des Forêts in Moroni at a regulated cost of 15,000 KMF per guide per day.
No public bus system operates on any island. Boat transport between villages on the same island is possible but uncommon except for fishermen's boats available for informal hire. The crossing from Grande Comore to Mayotte, the French overseas department to the southeast, is not a legal tourist route as Mayotte maintains separate immigration controls not aligned with Union of the Comoros entry procedures.
The dry season from May through October offers the most reliable weather, with minimal rainfall and temperatures ranging from 24 to 28 degrees Celsius. November through April constitutes the rainy season, with January and February receiving the heaviest precipitation. Tropical cyclones track through the Mozambique Channel between December and March, though direct strikes on the Comoros are infrequent. Humpback whales migrate past Mohéli Marine Park from July through October, with peak sightings in August and September. Mount Karthala's active volcanic crater emits sulfur gas that intensifies during humid rainy months, making the May-to-October window preferable for summit attempts.
Independence Day on July 6 brings government closures and public celebrations concentrated in Moroni. The Grand Marriage ceremony, known as Anda na Harusi, occurs year-round but peaks during the dry season months when wealthier families hold multi-day events costing upwards of 50,000 euros. These ceremonies close family compounds to outsiders but generate increased demand for guesthouses and taxis. Eid al-Fitr and Eid al-Adha follow the Islamic lunar calendar, with dates shifting eleven days earlier each Gregorian year. During Ramadan, most restaurants outside tourist hotels close during daylight hours.