将以下文本段落翻译为英语。
中文文本： 听说在海南岛有一个神秘的海滩，只有在退潮的时候才能露出来。许多人在寻找它，但没有人能够找到。它是否真的存在？这是一个谜。
English Translation: 

I heard that there is a mysterious beach on Hainan Island, which can only be revealed at low tide. Many people are looking for it, but no one can find it. Does it really exist? This is a mystery.