The New World Shopping Mall has been abandoned since 1999. It shut its doors after being condemned by local regulators. A few years later a massive fire destroyed the structure’s roof. Not long after that monsoon rains flooded the lower floors.

As a way to combat the spread of mosquitoes and other insects breeding in the stagnant water, locals introduced koi and catfish to the former mall. Not only did the fish take care of the pest problem, they’ve thrived. It is now one of the world’s largest urban ponds.

(via sincerelyshai)