The Kenyan coast strings Mombasa's Old Town and Fort Jesus (UNESCO), Diani Beach's south-coast strip below Tiwi, the Watamu Marine National Park, and Lamu's medieval Swahili town accessible only by dhow boat.
Two dry seasons (long dry July-October and short dry December-March) with Diani and Watamu at peak, Lamu Cultural Festival in late November aside, and reef visibility past 20m.
Short dry season with sea calmest, Christmas through New Year at peak resort demand, and the Lamu Yoga Festival in mid-March aside, hawksbill turtle nesting on Watamu beaches.
Long rains with afternoon storms, lower rates across Diani and Watamu resorts, but the coast stays warm at 28°C and the marine sites accessible between systems.
Lamu Cultural Festival late November brings Swahili poetry, dhow races, and traditional Maulidi celebrations on the Lamu archipelago, the coast's biggest cultural event.