Welcome!!!You didn't indicate where you were starting from, or which train you are taking to New Orleans. I assume you're taking the City of New Orleans to New Orleans, and the Sunset Limited from New Orleans to Florida. I can't answer your question about New Orleans, as I have never been there, but I hear the station is in a rather rough neighborhood.
Don't count on your trains to be on time. But don't count on them being late, either.
If you are riding coach you will be directed to a seat by the car attendant when you board. Once aboard, remain in your seat until a conductor comes to take you ticket. You shouldn't have to wait more than a few minutes. The conductor will place a tag called a "seat check" above your seat to indicate your destination and that the seat is taken. After that you are free to move about the train at will (except into sleeper cars). If you are curious about sleeping accomodations for possible future trips, ask someone to show them to you.
If you leave your seat it is advised to take cameras or other valuables with you, or at least keep them hidden in your bags.
You will be riding on double-decker Superliner equipment which offer great views of the countryside.
Rest rooms and luggage racks are on the lower level. The rest rooms are tiny, but the handicapped unit in coaches are huge and you don't have to be handicapped to use it. Faucets have been known to have too much pressure and often splatter. Now and then you'll find a car where the pressure is just right.
Seats are reasonably comfortable and offer ample legroom for sleeping. They recline and have both a leg rest and foot rest. Sort of like a lay-z-boy. Legroom is way better than anything you will find in almost any other vehicle, public or private. This allows you to recline without putting your seatback in someone's face, like on an airliner. There is storage space under the seat in front of you, and above your head. There is also an overhead reading light. Overnight you will get a small airline style pillow.
When walking on a moving train spread your legs a little farther apart than normal for better balance. Use the handholds when passing between cars. Always wear shoes when walking about the train. This is mandatory.
Food is available in two places. Table service with freshly cooked meals are available in the diner at specified hours. Quality is generally good, sometimes excellent, but can vary with individual chefs. Tip your server as you would in any restaurant. A cafe with a variety of packaged sandwiches, snacks, beverages, etc is also available on the lower level of the lounge car. This is open all day and usually closes at about 11:00pm. It is also closed during the attendant's meal breaks.
Stops and other information are announced over a PA system running through the train.
Talk to strangers. You'll learn things you never knew you didn't know. You'll make friends in short order.
Finally, my standard advice to first time Amtrak travelers is to expect to have fun, but don't expect perfection. This is Amtrak, not the Orient Express.
Good luck. Please report back after the trip and let us know how it went. We regulars here especially enjoy reading the impressions of first-time riders.
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Trust God, love your neighbor, and never mistake opinion for truth.
-Mr. Toy
The Del Monte Club Car
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Come on, Congress, you guys have no problem kicking out the cash to build highways that facilitate a four-hour driving time for the same journey...