one-horse town就指规模很小的乡镇；简朴小镇。

【例句】
This was a one-horse town, a beautiful quiet place.
这里以前是个乡村小镇，宁静而又景色秀丽。

I come from a one-horse town in the west. I've lived here in New York for 30 years, but I often think about going back to the simple life there.
我来自西部的一个小乡镇，在纽约已经住了三十年了，但是我还常常向往回老家去过那纯朴的日子。