This is the 733rd most frequent German word.
langen
To reach or to suffice.
The word 'langen' is used through its root form 'lange' here as an adjective describing the duration or length of the hike.
Ich habe vor, eine lange Wanderung zu machen.
I plan to go on a long hike.
Here, 'langen' is employed as a verb meaning 'to reach,' describing an action directed toward something.
Er musste nach dem Ziel langen, da es außer Reichweite war.
He had to reach towards the goal, as it was out of reach.
In this example, 'langen' appears as 'langen' in its inflectional form, functioning as an adjective, indicating an extensive duration or depth to the explanations.