PPO Plans provide nationwide health coverage if you travel out of your area - ANY Doctor ANY hospital in the country.
On PPO plans, you don't need to get a referral from your family doctor to see a specialist doctor, you can bypass that step with a PPO and make direct appointments with the specialist doctor of your choice.
Unlike an HMO, POS or EPO network plans which only provide limited or local coverage, with a PPO plan you are financially protected in a medical crisis anywhere in the country.