Introduction to the tide flat: The pigeon nest tide flat is a good place to observe modern coastal sedimentation. You can see wave marks, rain marks, cracks, biological caves and other sedimentary structures. The broad tide flat turns into a vast ocean in a short while. Viewing the sea from here, the magnificent masterpieces of nature make people proud, full of hope and ideals. When the tide recedes, the waves of sea water left on the tidal flats form beautiful pictures.