One person guards the lonely city, invincible in the world

After the An-Shi Rebellion, the Tang Dynasty collapsed and the Dao of Heaven changed dramatically.
A city hangs alone in the Western Regions, isolated for 60 years, the whole city is gray-haired, has never surrendered, and has never been captured.
Because this is the territory of the Tang Dynasty!
Gu Changan, who was born and grew up here, killed the enemy at the age of ten, and at the age of 20, only his lonely figure remained on the mottled and dilapidated city wall.
He was so tired, he was so desperate, but he couldn't fall.
……
After a lot of hard work, the news, more than 60 years late, finally arrived in Chang'an.
"There is still a piece of territory in the Tang Dynasty in the Western Regions, and the last Anxi Army is still guarding the Tang Dynasty!"
The Central Plains were shocked, and the world burst into tears!
The newly enthroned female emperor's phoenix eyes were red, and she burst into tears:
"He is the most beautiful scenery in the Tang Dynasty, and he is the last glory of the prosperous Tang Dynasty!"

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