The You Han Valley was at the northern side of the Inner Land. You Han Valley had Martial Emperor named Martial Emperor You Han.
The incomplete Han Bing's Divine Sword Technique that they cultivated had been secretly passed down by Martial Emperor You Han.
You Han Valley had a rule whereby the complete Han Bing's Divine Sword Technique could only be passed down to one person each generation. It had been an imperative rule since the beginning of time.
You Han Valley had seen 3,000 years of generations.
Throughout the 3,000 years, many Martial Emperor powerhouses achieved Martial Emperor Stage due to the cultivation of Han Bing's Divine Sword Technique.
Naturally, not everyone could achieve Martial Emperor Stage just by cultivating Han Bing's Divine Sword Technique alone as it would depend on one's talent too.