Jūnlǚ shī de dì-yī míngjù, dāng shǔ "Qín shí míng yuè Hàn shí guān".
The most famous line of frontier poetry is 'the moon of Qin, the pass of Han.'
Tips
history
From 《出塞》 by 王昌龄 (Wang Changling, Tang dynasty): '秦时明月汉时关，万里长征人未还。但使龙城飞将在，不教胡马度阴山.' Canonical 边塞诗 (frontier poem). 飞将 = 'Flying General' 李广 Li Guang of the Han — the poem laments that no Li Guang-like hero defends today's borders.
usage
This is an 'interlocking parallel' (互文) — the moon is of both Qin and Han, and so is the pass. Classical rhetorical device: don't read it as two separate ages.
