What is the significance of all the areas in this Pasuk?
Ramban: This is an itinerary of how Yisrael will enter into Eretz Cana'an. 1
Targum Onkelos: Incorporating a description of the various types of terrain that they were about to inherit
What is "P'nu u'Se'u lachem" referrring to?
Rashi (citing the Sifri) and Targum Yonasan: It refers to the road leading to Arad and Chormah. 1
Rashi (in the original manuscript): Which was next to Edom, close to Kadeish. See Sh'lach-L'chsa, 14:45.
Which area does each of the other types of terrain represent?
Rashi (citing the Sifri) and Targum Yonasan: "u'Vo'u Har ha'Emori" - to the area on the south-eastern border next to Edom; "v'el Kol Shecheinav" - to Amon, Mo'av and Har Se'ir; 1 "ba'Aravah" - to a stretch of forest-land; "ba'Har" - to the mountain known as 'Har ha'Melech'; "ba'Shefeilah" - to the lowlands of the south; "ba'Negev" - the desert-land in the south, 2 "u've'Chof ha'Yam" - refers to Ashkelon, Aza and Caesaria ("Eretz ha'Cana'ani"
Why does the Torah refer to the River P'ras as "N'har ha'Gadol"?
Rashi: Because it is mentioned in connection with Eretz Yisrael. 1