Most of the houses that can be seen today were built in the 19th century
when Zanzibar was one of the most important trading centres in the Indian Ocean region.
The coraline rock of Zanzibar was a good building material, but it is also easily eroded.
Many houses are in a bad condition and need repair.
The fascinating labyrinth of narrow streets and alleyways is filled with many small shops and workshops, selling art and souvenirs.