Bioluminescent algae along the shores of the Matsu Islands off the coast of Taiwan

© Wan Ru Chen/Getty Image

Blue tides at night. The glowing waters of the Matsu Islands

From April through September, a type of algae commonly called ‘sea sparkle’ blooms along the coast of all 36 islands in the Matsu archipelago off the coast of Taiwan. An enzyme reaction in the algae’s single-cellular bodies creates the light-emitting chemical reaction. Locals call the natural light show ‘blue tears.’ Stranger still is that when the water is disturbed, the algae light up even brighter. If you want to see the blue tears of the Matsu Islands, there’s still time to book a trip—the bioluminescent effect is more common and more intense during the hot summer months.