Hi folks! General hardware question, and I may be in over my head.

One of the prime camping locations at a nearby park is unfortunately
in a valley. This has the effect of radically limiting our GMRS
radios.

Would it be at all useful to run a mobile or base antenna about
50 feet up a tree and leave an antenna line so that we can just
plug in when we're at camp to get in contact with folks out
in the bush?

The amount of info out there is overwhelming. It seems like with
the tiny (~ 1W) radios, it's going to be important to get as
low-resistant cabling as possible.

Can anyone make a suggestion as to the right hardware for the job?
Is this a scenario where I'm going to need to "tune" an antenna?
Heck, is this even worth it?

Thanks!
WB