北窗一枕南城一梦
[bĕi chuāng yī zhĕn nán chéng yī mèng]
It conveys a dream-like quality with melancholy sentiments, evoking an image where someone, perhaps reminiscing or lost in thought about the good times spent in South City, lies against the window of North, having sweet or bittersweet memories like a beautiful dream, possibly representing longing and nostalgia towards a specific place, period, or event.