Learn German: Der Weg dahin war lang. - The way there was long.

da means "there" as a fixed location. Because a path or way (der Weg) implies movement toward a destination, German adds the directional word hin (meaning "away from the speaker"). So dahin literally means "to there." English just uses "there" for both location and direction!

Is there a difference between dahin and dorthin?

Not much! Both mean "to that place" and are used with motion. dorthin is a bit more specific and emphasizes the exact destination, while dahin is slightly more casual and very common in everyday speech. You could absolutely say Der Weg dorthin war lang.

Why is dahin right next to Der Weg? Doesn't the verb have to be in the second position?

The verb war is in the second position here! In this sentence, the entire noun phrase Der Weg dahin (The way there) acts as a single block of information—the subject—which takes up the first position. Because dahin describes the noun Weg, it stays right next to it.

Does this sentence refer to a physical road, or can it be figurative?

Just like in English, it can be both! Der Weg dahin can mean a literal physical journey, or it can describe the figurative process of achieving a goal (like learning German).