Albert Barnes Commentary Joshua 13:4

"on the south; all the land of the Canaanites, and Mearah that belongeth to the Sidonians, unto Aphek, to the border of the Amorites;" — Joshua 13:4 (ASV)

Read on the south, and connect the words with the verse preceding. They indicate the southern limit of the still unconquered territory in this neighborhood, as Joshua 13:3 gives the northern one.

Mearah - The cave (see the margin) has been referred to “Mugar Jczzin” (“cave of Jezzin”), between Tyre and Sidon, or to a district characterized by deep cave-like ravines near Sidon and Dan-Laish.