No, you do not need a passport to fly from Kentucky to California, as both states are within the United States. However, you will need to present a valid form of identification, such as a driver's license or a state-issued ID, when going through airport security. Make sure your ID is compliant with TSA requirements.
You do not need a passport to fly from Los Angeles, CA to Denver, CO. As long as you are a US Citizen, the only identification you will need is your driver's license or state issued identification card.
Whenever leaving the US (and returning) it's always best to have your passport readily available.
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If you are a US citizen, you do not need a passport to go between any two states including California and Hawaii. Foreign visitors need to show their passports when traveling between any two US cities by air.
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You would need to fly into either Burbank or LAX. It will be approx. 3 hours from Atlanta.
It is 2,085.55 miles according to MapQuest.
12 hours
168$
How many hours to fly from Delta ca. to Oklahoma city?
From Louisville to Bucharest: ca. 9 750 km (ca. 6 000 miles).