TT #4 · Parashas Va’eschanan · First Aliyah · Passuk 3:25
Let me cross over, please, and see the good land that is on the other side of the Jordan, this good mountain and the Lebanon.
Torah Temimah points to the classical identification of “the good mountain” with Yerushalayim (and Lebanon with the Beis HaMikdash), drawn from Sifre and parallel midrashic traditions.
Sefaria — Sifre Devarim (related)
English: “This good mountain” — this is Yerushalayim. “And the Lebanon” — this is the Beis HaMikdash.
Custom (midrashic identification of geographic terms with Yerushalayim and the Mikdash).
When Moshe asked to see “this good mountain and the Lebanon,” he was asking to see Yerushalayim and the Beis HaMikdash — the spiritual core of the Land he longed to enter.