Liv,
Welcome to Travelblog! Your itinerary looks very nice, with lots of great areas. Its also fast paced in the first part, which means you'll see lots of stuff but won't have much time at each one. You'll also spend lots of time on transport. Many people have done trips like this and enjoyed them; it all depends on the type of experience you want.
Some specifics (apologies for the length):
1. The current itinerary goes from Los Angeles to Las Vegas and back to the Los Angeles area. It also puts you in Las Vegas on a weekend, when hotel rates are 35% higher than during the week. You'll save transport time and budget by seeing Las Vegas first. Make sure you can get a Grand Canyon flight from Las Vegas during the week that time of year, though.
2. Las Vegas production shows are amazing. Cirque du Soilel is a must see. If you are willing to see a less-popular production (Mysterie instead of O, for example) the Las Vegas Convention and Visitors Bureau runs a service that sells last minute tickets at high discounts (up to 50%!)
3. Los Angeles is a truly vast metropolis, hundreds and hundreds of square miles. This makes for very long transport times. Downtown to Hollywood, for example, is over an hour, and to Santa Monica can take four or more on a bus.
4. Universal Studios is a theme park with a studio tour attached. As a theme park, its great and a nice complement to Disneyland. To actually learn about movie making, Paramount or Warner Brothers are much better (Paramount is easier to get to without a car, FYI). Both now have extensive security checks, so reserve as far in advance as possible.
5. Seeing Disneyland while staying sane requires extensive planning. The lines are very long. If at all possible, visit during the week. Seeing everything, incidentally, will require three full days.
6. Renting a car in Newport means dealing with Los Angeles traffic. The city is so huge it can't be avoided. The expressways have a minimum of six lanes each way, and the local roads often have three or four. Trying to find a rental in Santa Monica may be a better bet, since you can directly hop on the Pacific Coast Highway. The other option is to fly or take the train to Santa Barbara and pick up the car there.
7. Three days for LA to San Francisco is really pushing it, especially if you like natural scenery. It can certainly be done, but all you'll do is watch through the car windows. Big Sur is one of the greatest scenic areas in the world. At a minimum, take the time to hike to McWay falls (under an hour) and stop at the numerous pullouts.
8. For wildlife, visit Port Lobos Reserve south of Monterrey. Allocate at least a few hours. For even more, visit the Monterrey Bay Aquarium, one of the best in the world.
9. If you have the flexibility, I would swap Yosemite and San Francisco. This neatly avoids the parking problem.
10. Lodging reservations for Yosemite need to be made immediately, as in as soon as you read this. They sell out within weeks or even hours. Unless you are camping, expect to pay high rates inside the park.
11. Fisherman's Warf is fun, but also a huge tourist trap. The city's history museums are much better.
12. Alcatraz tickets need to be bought at least a week in advance.
13. If you can find the time, a visit to a redwood park is a transcendent experience. These are the tallest trees in the world and among the oldest. Muir Woods is closest to San Francisco and can be done in a day.
14. Memphis has the history of Rock and Roll, plus Elvis. Nashville has incredible country shows and music history. Both are much better than Dallas. Memphis can be seen without a car.
15. Currently, Washington DC has only two days. Depending on how much you like them, the museums alone could take a week. Unless you want to see lots of Broadway shows (which get expensive fast), I would drop a day or two in New York to get more time in DC.
16. Unless you have your heart set on a specific show, last minute day-of-show Broadway tickets can be bought from the TKTS booth in Time Square for 50% off or more.
17. For transport, California is stereotyped as the state of the convertible, but for a reason. The weather is warm, and not having a roof shows off the incredible scenery. I have always found driving one worth the extra rental cost.
Your trip will be an incredible experience. Please remember to blog it.
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