Inutile loveliness" is kind of the key word of Nabokov's technique, and he says the novel has as its only purpose to provide aesthetic bliss. So, here is inutile loveliness coming just from seeing the landscape as a stranger.

无用的可爱“是纳博科夫技巧的一个,关键词，他说小说只有一个目的，那就是提供,美学狂喜，所以这里的“无用的可爱“,是把风景当做一个陌生人看待。

耶鲁公开课 - 1945年后的美国小说课程节选