Introduction to the Undersea Tunnel: The Undersea Tunnel is 86.2 meters long and 2.5 meters wide. It is an annular enclosed space made of 20 cm thick arched acrylic glass imported from abroad. The ground part of the tunnel is an escalator. Visitors can stop and visit while standing on the staircase, just like admiring the birds flying freely in the sky. Through the acrylic glass of the undersea tunnel, we can also see various sharks: nurse sharks, leopard sharks, Japanese whisker sharks, black tip sharks, white tip sharks, etc.