The largest and most technologically advanced ship of the ancient world: the Chinese junk

A CHINESE JUNK UNDER FULL SAIL
Originally uploaded by Okinawa Soba

A junk is a Chinese sailboat design dating from ancient times and still in use today, says Wikipedia.

It was by far the largest ship design in ancient history and was technologically superior to European and other Asian designs.

Junks were developed during the Han Dynasty (220 BC–200 AD) and were used as ocean-going vessels as early as the 2nd century AD. They evolved in the later dynasties, and were built and used throughout Asia for extensive ocean voyages.

They were found, and in lesser numbers are still found, throughout South-East Asia and India, but primarily in China, perhaps today most famously in Hong Kong.