hi,

planning on doing a lot of hiking in the national parks for a couple of months and would really like a cell phone prepaid sim card for the trip. we will be mainly on the west coast but also yellowstone. which provider would suit my needs best, with best coverage.

i have an unlocked tri-band cell phone.

Only T-Mobile and Cingular uses the GSM network, so those are your only choices. In many rural areas, there's only 850MHz coverage and no 1900, so if you phone doesn't have 850, you'll find service spotty to non-existent.

Looking at the prepaid service area on Cingular and T-Mobile's website, you'll not get service at Yellowstone.

I'm not sure you'll get any service if you're too far from a tower no matter how many bands your phone has or uses.

I have Verizon and could get cell phone service at Old Faithful and Mammoth Hot Springs...but not much else in Yellowstone.

I get spotty service in Yosemite Valley..just waking from one campsite to another can make that much difference! I've made calls from the top of Vernal Falls.

This last year was the first time we could make calls from Zion National Park, Utah near the visitor center, but I don't think we had service farther in the canyon.

I had no service in Capitol Reef National Park, and I've heard others complain about this area too.

Utahtea

In Tuolumne Meadows (Yosemite), and all our hikes in that area, we had no coverage with either Cingular or Verizon.