Anxiety Island Introduction
About 2 kilometers north of Da-Bai-Sha Island, there is a typical square mountain-shaped island, which is mostly composed of large stone slabs that are flat and smooth, resembling a blacksmith's anvil; hence it is named Anvil Island. The island is about 5 meters high, surrounded by vertical sea cliffs. Besides the anvil-shaped basalt at the highest point, there are many uniquely shaped honeycomb rocks. It also served as a shooting range for the military in the 1960s, resulting in remnants of metal sheets and rock fragments. Anvil Island is located offshore in the northwest of Penghu Island, entirely made up of basalt, and its shape closely resembles that of an anvil, leading to its name. Due to the northeast monsoon in winter, the waves have long eroded the northern coast of Anvil Island, forming the largest sea cave in all of Penghu, measuring over 10 meters in height. This cave has a unique location where sunlight cannot reach it throughout the year, causing the temperature inside to be about three to five degrees lower than outside even in summer, frequently attracting visitors to seek refuge from the heat, thus earning the name "Air-Conditioning Cave." From the northern sea, one can clearly see that the upper part of the island's cliffs is basalt, while the lower part consists of volcanic gravel rock. Due to the fragile nature of the volcanic gravel rock, it has been eroded by winter waves, creating a massive sea cave beneath the northern cliffs where small yachts and fishing boats can enter. The intertidal zone on the island is relatively shallow and short, with almost no wave-cut platforms near the sea cave; only on the eastern cliff is there a platform about 5 meters wide and a small area of pebble beach to the south and west, so there are fewer fishermen harvesting snails and shellfish on the island. As a result, each year, thousands of Black-faced Spoonbills come to the island to breed. Whenever boats approach the shore, flocks of Black-faced Spoonbills take off from the island and emit low, dog-like warning calls, finally gathering in the sky above the ships, creating a truly marvelous spectacle.
