Underwater world

The arch is made of special kind of steel which offers protection from ships weighing up to 4,000 tons.

In order to protect the inscriptions from erosion, experts from the Institute of Archaeology of the Chinese Academy of Social Sciences used resilient ethyl silicate to reinforce the carved stone.

It took seven years－from 2003 to 2009－to build the underwater museum at a total cost of 210 million yuan ($30.88 million).

There are a total of 3,800 tons of water in the container. And the museum has 23 viewing windows allowing around 40 visitors to view the ridge at the same time. It also has 28 underwater cameras, enabling visitors to zoom in and out using touch-screens.

Visitors are also allowed to dive into the container to explore the works up close.

Over the past decade, the museum has worked with Chinese universities and tech companies to develop new technologies to protect the cultural relics.