这是博物馆里游客最少的展厅，展览着一些最不为人知的艺术品。

This is the museum's ___least-known gallery, displaying some artworks recognized by very few people.

这片区域是这个国家最少为人所知的部分，甚至连导游都不熟悉路线。

This area is the ___least-known part of the country, even tour guides aren't familiar with the routes.