St. Mary's Cathedral, on the old Kaloum peninsula a few blocks from the Presidential Palace, is the seat of the Archdiocese of Conakry and the principal Catholic church of Guinea. The building dates from the early 20th century, when Conakry was capital of French Guinea, and the simple French neo-Gothic facade — a single bell tower, lancet windows — is one of the better-preserved colonial buildings in the city.
The interior is unadorned and quiet, with original wooden pews and a small choir loft. Guinea is overwhelmingly Muslim — Catholics make up perhaps 5% of the population — but the Sunday services here are lively, with strong choral singing. Visitors are welcome outside service times; ask the caretakers at the side door.