China was during the Ming Dinasty and until the early XIVth century the greatest naval power. The largest vessels of the Ming Dinasty are reported to have been up to 400 feet long and composed of up to 9 masts!
A brief account of the Voyages of Zhen He:
Traditional History: The Ming Voyages
Another brief account:
European Voyages of Exploration - The Ming Dynasty
But an imperial decision to limit the lenghts of these sea voyages, in an attempt to prevent any foreign influence entering China, gave Portugal the lead over the seas, starting the Age of the Discoveries and the start of Europe's dominance and expansion in the World.
By the way, the magnetic compass, so usefule in navigation, is a Chinese invention of which the first reference is found in the early years of the first millenium. This Chinese compass pointed to the South, not to the North.
An early Chinese compass

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'Dardanidae duri, quae uos a stirpe parentum
prima tulit tellus, eadem uos ubere laeto
accipiet reduces. Antiquam exquirite matrem:
hic domus Aeneae cunctis dominabitur oris,
et nati natorum, et qui nascentur ab illis.'
We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light.
–Plato–
'Many people, I believe, wish for a society where faith, decency, pro-life convictions and national self-determination within Europe can flourish; and not be swallowed up in a dictatorial EU bureaucracy.'
–Gerry McGeough, Irish Nationalist and POW–