李益 不知何处吹芦管， 一夜征人尽望乡。 Somewhere comes a flute's sad tunes ('neath the starry dome); All night long, all the soldiers are longing for home!

【夜上受降城闻笛】    唐 • 李益            
 
回乐峰前沙似雪，    
受降城外月如霜。
不知何处吹芦管，    
一夜征人尽望乡。
 

Ascending At Night (the Battlements of) the City-Accepting-Surrenders and Hearing A Flute       
-- by LI YI (748-827; mid-Tang dynasty)  
-- Translated by Frank C Yue


Below the Huile Mountains the sands gleam like snows; 
Beyond City-for-Surrenders, like frost the Moon shows.
Somewhere comes a flute's sad tunes ('neath the starry dome);
All night long, all the soldiers are longing for home!

 
Notes:

1.  受降城：唐代有东、中、西三座受降城，都在内蒙古自治区境内。

2.  回乐峰 :  A peak of a mountain in the SW of Lingwu in the Lingxia province.