Travel advice filter – planning a trip which will take me via Canyonlands, Bryces and Zion NP to Las Vegas, and from San Francisco to San Diego.

Wow, there's really no time in that itinerary for unexpexted problems, or staying longer anywhere fun. I'd end it in San Francisco, and give yourself more time in Zion and SF. Or something like that. Yosemite at that time is not the best- it will be hot and dry as hell. It's better early October once Autumn starts to set in. I think you've just got too many deadlines to meet with all the airports, and not enough wiggle room. I'd say cut the number of destinations in half, and you'll get more out of the trip.

I disagree with oneirodynia about Yosemite's weather in September. The average high in September is 86, with a 52 degree low. There is a chance that you'll get mid-90 degree weather. There is just as good a chance that you'll get unbelievably beautiful 80 degree weather. There is plenty of shade in the valley and even when it's hot, it only stays that way between 1:00 PM and 6:00 PM. Do not let worries about the weather deter you from Yosemite in September. It's not only hot, the waterfalls are a mere trickle, and the Valley is full of smoke from all the burns. If a bit of trip has to go, I'd definitely leave out Yosemite in September. I think it's the worst month to visit that particular park. Even the bears are extra hungry and cranky.

To clarify, Labor Day in the US is the last weekend of the summer travel season, so Yosemite is really, really crowded. Again, it doesn't sound like this will be a problem with the timing of your trip.

I think you're spending too much time driving on days 12-14. I'd strongly suggest that you do the drive as an overnight. Whether you drive down the coast (which I'd recommend with GardenGal's notes) or Highway 395, don't take more than 2 days to do it. Spend the extra day in San Francisco, Yosemite or one of the other National Parks. Also, if you do drive down the coast, consider cutting over to I-5 at San Luis Obispo. The coast is nice past that point, but you're essentially seeing more of the same, and it's slow going. The down side is that you will run into ugly traffic in LA between 3:00 PM and 7:00 PM. I disagree with oneirodynia about Yosemite's weather in September. The average high in September is 86, with a 52 degree low. There is a chance that you'll get mid-90 degree weather. There is just as good a chance that you'll get unbelievably beautiful 80 degree weather. There is plenty of shade in the valley and even when it's hot, it only stays that way between 1:00 PM and 6:00 PM. Do not let worries about the weather deter you from Yosemite in September. It doesn't sound like this will be a problem, but you don't want to be in Yosemite on Labor Day weekend on September 1. Consider flying from Las Vegas to Fresno, renting a car there and going directly to Yosemite. (There is nothing to see in Fresno). Then, after you've left Yosemite, go to SF, down the coast and on to San Diego. If you're going to drive down the coast anyway, you'll save one leg of the boring 3.5 to 4 hour drive back and forth from Yosemite. You could return the car in SF and pickup another one when you leave the city to keep costs the same.

Thanks everyone. That's plenty of food for thought :)

Ooh! My home digs! Days 12-14, when you're driving down to San Diego: You MUST drive Hwy 1, which goes along the cliffs over the coast and is (I believe) the most photographed scenic highway in the US. It goes by several must-see things. - Stop in Monterey to see the Monterey Bay Aquarium, best in the world. - Stop in Carmel (10 minutes south) for the huge white sands beach and long stretch of tiny boutiques and fancy restaurants (be sure and get a tourist guidebook, because they're all good and how will you choose otherwise?). - Drive an additional 15 minutes south to Point Lobos National Park and take a quick 1 hr easy hike along the sea cliffs. You'll see seals, otters, all kinds of birds, great rock formations, startlingly blue inlets. Gorgeous. - Then drive on down another 1/2 hour to Big Sur. Stop and have lunch/dinner at Nepenthe's while you watch the ocean crash and roll a mile below you. Go to a wine tasting at Bonny Doon vineyards. - downtown San Luis Obispo (about 2.5 hours south of Monterey) is also charming, and a good place to stop for lunch. If you're lucky it'll be a Farmer's Market, which is very large and totally worth a stop. Ah, I miss California. :)

I have to agree with oneirodynia, I think you are going to come back with lots of great memories of things you've seen through the windshield of your rental car, and not much actual fresh air exploring. I've done trips like this around the southwest, and you get a great list of places to say you have been, but not really any quality time anywhere. Personally I suggest slowing the whole thing down, cut off everything after Vegas, and instead end by driving or flying to LA and fly back to London from there. That way you can spend more time in great places like Zion, and you aren't beholden to airline reservations if you want to change your plans a little. Next time you visit this area, do the coastal trip on PCH, its deserving of a trip of its own.

Of course you can't do everything, but if you find the time do the Island in the Sky division of Canyonlands. That's the part of the park between the two rivers (Colorado and Green). From Moab you have to travel quite a way upstream to get to a bridge, but once across you can drive right down the ever-narrowing strip of land to the point that overlooks the confluence. It's spectacular, and since not many people are willing to make the trip, you may very well have the point all to yourself. (My girl and I did). Many times since then I've looked down on that point from an airliner overhead, and looking at the surrounding terrain you realize what a privilege it is to have been there. One tip: when driving on unimproved washboard roads in Utah, let a little air out of the tires. You'll get a better ride and make better time.

Bryce is striking, but Capitol Reef has a lot more variety and a lot more to see IMO. Plus it's less developed/touristified/narrated/mediated.