Tong Vey was a Klingon city on Qo'noS.
Emperor Sompek sieged Tong Vey and ten thousand warriors later conquered the city. The victorious Sompek soon ordered that all of the inhabitants of Tong Vey be killed. (DS9 episode: "Rules of Engagement")
In the mirror universe, Sompek's victory at Tong Vey is celebrated in the opera Sompek's Revenge. (ST novel: Dark Passions)
In 2387, Tong Vey was featured in a travel guide about the Klingon Empire. (ST reference: Hidden Universe Travel Guide: The Klingon Empire)