There are a ton of places to see in San Fran, but I can also recommend getting up into the Wine Country and doing a visit to Calistoga. There is an awesome vineyard there called Sterling Vineyard or Winery that has a beautiful aerial tramway ride to the top of a hill where they do their wine processing. On the ride up you get to see the gorgeous vistas (vine covered rolling hills, etc) and it’s just a pretty place to sit, relax and enjoy (oh and I’m NOT a wine fan, so you don’t have to be into wine to enjoy it, but from people I know, they like Sterling, so it’s win-win!). Also right by that vineyard is the “Old Faithful Geyser of the West Coast”! It’s one of 3 (Yellowstone’s Old Faithful being the most known) geysers that are regular enough to be called old faithful. The area itself is gorgeous to drive through as well. 🙂
Vegas has it’s obvious attractions of bright lights, gambling, shows, etc, but it also has some really nifty things to see within a short drive away. For instance Valley of Fire State park is just within an hours drive away and is fantastic! It literally has a rainbow of colors embedded in the rocks/ground. The only thing to note on that is that it’s named Valley of Fire for a reason, so if they aren’t travelling there during the winter time then I personally would recommend making sure that they have a car with a good air conditioning system! You can see much of the beauty of the park without actually getting out, so during most of the year, I’d recommend just driving around through it and not trying to hike/walk anything. Also very nearby Vegas is Hoover Dam. It’s got some breathtaking vistas and it’s an interesting tour as well!
Arizona is one of my favorite states. If they are going to be in Phoenix for any length of time, I’d recommend driving up to the Grand Canyon, Painted Desert/Petrified Forest, Montezuma’s Castle. We did all that in just a couple of days (it’s a fair bit of driving but sooooo worth it!). If they have more time, then add in Walnut Canyon State Park (better the Montezuma’s Castle to see cliff dwellings if you are willing to hike!), Wupatki National Monument/Sunset Crater, and Sedona’s Red Rocks (the Pink Jeep tour is awesome!). I love all kinds of nature and these spots are awe-inspiring to me!
I didn’t spend too much time in Miami other then for a spring training baseball game or too, but it’s so close to the Everglades! Just a short drive (you can probably find a tour easily enough that leaves from there as well) and you have a bunch of airboat tours to choose from to see the swamps. We’ve done about 3 of them now and they’ve all been fairly different from each other and all were very neat to do! Another thing to see while in Miami, is the Florida Keys. Just be prepared for the fact that it is one lane in, one lane out and if there is an accident or a lot of traffic, the journey in or out can be fairly slow. It’s definitely worth the trip though in my opinion!
As for LA, my in-laws were here visiting for the first time, and one of the things they loved the most was going on a whale watching tour! We didn’t see any whales, but we saw an amazing amount of dolphins and it was just so cool to see SOOO many of them surrounding the boat! I’m also a fan of the Aquarium of the Pacific in Long Beach, and Santa Monica’s 3rd Street Promenade. Oh and the La Brea Tar Pits (though in all honesty it’s been YEARS since I’ve been there!). If they have time for a drive down to San Diego, it’s worth it. It’s prettier then LA, and has a ton of neat museums as well as the San Diego Zoo. I will admit though, that as much as I love the San Diego Zoo (and I was there in October so these aren’t 20 year memories or anything) I prefer the Wild Animal Park which is in Escondido. You can take harbor cruises, check out Sea World, enjoy the Gas Lamp Quarters.