The site above speaks of historical Jerusalem and Israel under international law, but ultimately it does not illustrate the boundries of ancient Israel nor does it compare the ancient kingdom's geography to that of the modern state.
Overlay the two maps in these links, and you'll get a decent idea of the differences.
https://en.wikipedia.org/wiki/Ancient_Israel
https://en.wikipedia.org/wiki/Israel
As can be seen here, the ancient Israelite kingdom had substantial tribal grounds as far north as Tyre, and east of the Jordan River - about 30% of what is now Lebanon and 20% of modern Jordan were under the control of the Israelite tribes until the exile of the northern Israelite Kingdom by the Assyrian Shalman'eser, ending the reign of Hoshea ben Elah (the story can be found in the first book of Kings). Also, much of the Negev, while considered holy ground, was not actually under Israelite control, but home to nomadic tribes of Edom, Amalek and Midian. The Golan Heights, which are under Israeli control today, was part of the kingdom of Og and the Bashan, until it was conquered by the tribes on their way to the land of Canaan, and after that was claimed by half of the tribe of Menasheh (Menasseh). The ancient Philistine kingdom, which the Israelites struggled to drive away, took up 45 miles of the Mediterranian coast from Gaza to Ashdod (with some of their military outposts as far as the Gilboa mountains). Most of what was the ancient Philistine kingdom is now within Israel's borders (indeed, of the five great Philistine cities, only Gaza is currently not in modern Israel).
As for me, I grew up in ancient tribal boundries, in what was known in ancient Israel as Emek R'fa'im - the boundry between the tribal grounds of Judah and Benjamin, where Saul met David.
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I should add a little - the tribes of Reuben and Gad were east of the Jordan. As I've already stated, the half of the tribe of Menasheh was situated an area slightly bigger than the Golan (it included some areas in modern day Jordan and Syria). The tribes of Asher and Naphtali extended further north into Lebanon than modern day Israel.
