How we cite our quotes:
The deer had led him deep into the Spine, a range of untamed mountains that extended up and down the land of Alagaësia. (1.4)
Just as the deer leads Eragon deeper into the Spine, we follow Eragon deeper into the world of Alagaësia. (See how Paolini did that? Pretty nifty, right?) As he encounters and learns about new lands and cities, so do we. His explorations become our explorations. Yeah, we're explorer-buddies.
Before him lay the Palancar Valley, exposed like an unrolled map. The base of the Igualda Falls, more than a half-mile below, was the northernmost point of the valley. A little ways from the falls was Carvahall. (2.8)
As Eragon takes in the scenery of his homeland, it's important to realize that the details are for us, not him. After all, he lives here, and knows that Carvahall is close to Igualda Falls the way he knows the back of his hand. We're the ones that need to see this detailed orientation like an "unrolled map." This kind of spatial detail adds a feeling of reality to what is fundamentally a supernatural setting (though, the elves and dragons haven't shown up just yet).
It unnerved Eragon how flat everything was […] He had lived his entire life surrounded by mountains and hills. (17.9)
Part of exploring is leaving your comfort zone. The plains that Eragon is seeing here for the first time are a strange sight in that it's something totally new and foreign to him. He's setting foot in a new land for the first time, which can be both exciting and nerve-wracking.