Trying to identify a movie phenomenon...

So in certain movies, there is a place that the characters are trying to get to; or one they end up at. Always a physical place. A destination that is regarded as the last hope, the final stand, usually in the face of near impossible odds.

I am looking for two things:
What is this phenomenon? theme? motif? (<—best word for this?) called?

I need some more examples!

Examples!

SPOILER ALERT
plot info for movies you maybe havent seen follow:

In I Am Legend they believe there is hope (to the north?). Ends up being at Bethel, VT

In Book Of Eli there ends up being a museum/safehouse inside Alcatraz prison where the worlds treasures are being amassed and safeguarded. (The Holy Books, art masterpieces, etc)

In Children Of Men the characters are hoping there is a real thing called “The Human Project” that they can get the miracle child to and try to save the human race. (although this one isnt really a place, but still what I’m looking for.

In The Matrix humanity’s last underground city is called “Zion”.

In The Lord Of The Rings they make a stand at Helm’s Deep, kind of the same idea, although the preservation of society element isn’t present.

PS I am a prodigal jelly from a long time ago, I searched and searched and then remembered the obvious answer would be to tap the collective!

Thanks Jellies!