Following recent heavy rains in Istanbul, a massive phytoplankton bloom has transformed the iconic Istanbul Strait from its usual deep blue to a striking turquoise. This natural biological phenomenon occurred as microscopic algae rapidly multiplied across the water’s surface in the wake of torrential downpours. The dramatic color shift has captivated both local residents and tourists, creating a rare and picture-perfect scene. Stunning aerial views have captured the full extent of this vibrant visual spectacle flowing through the heart of the city.