An old shopping mall in Bangkok is now an amazing koi pond.

Travel writer Jesse Rockwell stumbled on the mall when he was visiting Thailand last year. He wrote about the experience on his travel, food, and photography blog.

The seven-story mall was abandoned after a fatal fire in 1999, according to Rockwell. The basement floor became covered in water.

About a decade ago, someone introduced a small population of fish to the water. Today, the mall has become a "amazingly populated urban aquarium."

Rockwell said that the mall is difficult to find, and locals often discourage tourists from visiting.

He managed to take these amazing photos.

The sign outside the door reads "do not enter," according to Rockwell.

The escalator is now in decay and partially submerged in water.

The abandoned mall is now an amazing urban aquarium.

Rockwell posts about the experience at length on his blog.