At glacier national park visitors center
The going to the Sun road is blocked by snow until mid summer so you need to find out f it will be open if that's what you want to do
The visitor center will tell you where to go.
There are some at Lake McDonald and Apgar visitor center.
There are multiple pick up locations on the east and west side. Lake mc Donald, apgar visitor center and west glacier koa. Good luck enjoy!
I dropped my group at the visitor center. They got on the bus from there. Check in at the visitor center and they will direct you.
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