OK, you need to check a map - the distance from Denver [and Rocky Mtn NP] to Carlsbad Caverns will take a the better part of a day.

IF you absolutely want to do both areas, fly into one city {Denver or ABQ} and fly out of the other. Rental cars are going to be expensive, with a one way, drop off fee and you will need a big vehicle for 5 plus luggage.

I would suggest picking one state for this trip, there is plenty to see and do in each.

If you come to NM, do NOT skip ABQ, there is lots to see and do in ABQ. You could do a night in Carlsbad area, then 3 in ABQ [with some side day trips perhaps] and 3 in Santa Fe[with a day trip to Taos].

You need to do a bit more homework, come back and ask again when you have firmed up you route. Lots of info here, use the search box for ABQ or Santa Fe info.

Look into flying into Albuquerque instead of Denver and figure in the cost of renting a car that is large enough for family and luggage in each place. The last trip I took to Denver, the rental car cost was more than the air fare for two from the east coast. That said it would be about 400 miles, mostly interstate, from ABQ to RMNP. ( It would be farther from DEN to Carlsbad and not all interstate)

Carlsbad is interesting, but is quite far from the other places you want to see so I would save it for another trip.

Seven days could be spent just in RMNP, if you want to do a lot of hiking, in which case I would go into DEN just to save car time.

From ABQ I would look at going up to Santa Fe, to Bandelier and/or Tent rocks, up to Mesa Verde for hiking and history, back to ABQ.

There are lots of other routes you could take that involve very interesting things to see. If you want to see some pictures from these areas for trips that started in both places and were about a week or 10 days long you can look at mine at www.flickr.com/emalloy2009/sets in the 2008,2009, and 2010 sets.

Have a great time planning and going.

I agree that Carlsbad is going to be a really long detour from everything else you want to see. If you can leave that off, you'll have a chance to fit in RMNP but it's going to be days in the car to do both.

If Carlsbad is a main goal, then just make it a NM trip.

If you can drop Carlsbad, then one option would be an open jaw trip into Alb and out of Denver. Personally, I'd spend one night in Santa Fe, drive up to Durango over high desert, spend two nights in Durango, visit Mesa Verde NP (amazing, IMO) and maybe do the Durango-Silverton train ride (incredible scenery over the Animas river), drive up to Estes Park (this would be a long driving day) and then settle in at RMNP / Estes Park for three nights to enjoy the mountains.

If the openjaw/ rental car drop rate is too high, then you could fly into Denver and spend all of the time in the mountains at RMNP or do a "loop drive" around Colorado. I've done this several times and I love it. Near Denver you can see Garden of the Gods, Pikes Peak, even Cripple Creek, drive down to Alamosa and visit Great Sand Dunes NP, over to Durango and back up to RMNP and fly back out of Denver.

In 7 days you are going to have to make some choices. It will be hard (and a lot of driving) to fit Carlsbad in with the rest you want to do.

With 3 active teenagers who want to do things you will have more time together if you concentrate on one area. By covering just Carlsbad Caverns and Rocky Mountain NP you rack up over 1,500 miles, round trip from Denver plus going to attractions off the route. The temperature in the Carlsbad area hover above 90 in June. At Denver you can expect the hi 70s or lo 80s. And, as you go up the mountain it'll be cooler. And, as starrs mentioned there is a lot to see in Colorado. A suggested itinerary...

Denver to Rocky Mountain National Park, taking Trail Ridge Rd so you can hike at the top - abt 12,000 feet. Then to ...
Arches National Park and maybe nearby Canyonlands NP then...
Mesa Verde NP to hike among the cliff dwellings of ancient cultures. Then...
Durango, if you have time. This train ride is considered the most scenic train ride in the US, however the teenagers will be sitting most of the day except the 2 hour lunch break....
Great Sand Dunes NP They'll see the biggest sand pile they've ever seen -- 750 feet tall...
Colorado Springs has the US Air Force Academy, Olympic training center and the Garden of the Gods... And Pike Peak is nearby
You can get an idea of this at www.drivecrosscountry.net/RouteG1
This is about 1100 miles.

I agree with the rest that taking in both Rocky Mountains and Carlsbad Caverns is a lot for a 7 day trip.

You are also going to be traveling on the Memorial Day Weekend so be forewarned, you DO NOT WANT TO BE at Carlsbad Caverns on the holiday weekend. It might seem like it is out in the middle of now where but we were there on the 4th of July weekend about 20 years ago and we waited HOURS in line to ride the elevators back up! It's a popular place on holidays!!!

Utahtea

It's been a while since I posted, and yes, I really needed to do my homework. We have now decided to just do a week long Colorado trip. We are flying into Denver on May 29 and will depart June 6, renting a van for transportation. I would really like some route and lodging advice. We plan to make first stop Estes Park and spend two days at RMNP. Next is Colorado Springs (Pike's Peak, Garden of the Gods, Air Force Academy, Royal Gorge bridge), then on to Great Sand Dunes National Park.Next, we were thinking of Mesa Verde NP and Colorado Natl Monument. We are aware how cool it will be, and I wondered if it's too cold to try rafting at Royal Gorge. At any rate, if anyone has ideas on lodging (my kids love indoor pools and we go for the included continental breakfast)or other tips, I welcome them. Thank you!

You are flying in on Sunday of Memorial Day weekend, so you might have a hard time finding lodging that first night.

With only 7 days, I think you are still biting off a little too much. This is what you are currently looking at:

Day 1 Estes Park - approx 75 miles
Day 2 Day in RMNP
Day 3 Estes Park to USAFA, Pikes Peak Colorado Springs, approx 150 miles
Day 4 Colorado Springs to Great Sand Dunes National Monument, approx 175 miles
Day 5 Great Sand Dunes to Mesa Verde National Park, approx 235 miles
Day 6 Mesa Verde to Colorado National Monument, approx 235 miles
Day 7 Drive back to Denver, approx 280 miles

Utahtea

I think your children with be enthralled and fascinated by Carlsbad Caverns.

Since you have only seven days, I suggest you skip Albuquerque.

In Santa Fe we enjoyed the walking tour offered by the New Mexico Historical Museum, but a tram tour may be more appropriate for your family.

In Old Santa Fe, the San Francisco Street Grill (50 E San Francisco Street) serves large portions of very good food at reasonable prices--and in a comfortable dining room. Also, nearby, Tia Sophia's is a casual place and a local favorite for great delicious New Mexican food. We ate what our waitress suggested, and she was right!

If you have the time, it is very worthwhile to visit Taos and the nearby Taos Pueblo.

HTTY

I think your children with be enthralled and fascinated by Carlsbad Caverns.

Since you have only seven days, I suggest you skip Albuquerque.

In Santa Fe we enjoyed the walking tour offered by the New Mexico Historical Museum, but a tram tour may be more appropriate for your family.

In Old Santa Fe, the San Francisco Street Grill (50 E San Francisco Street) serves large portions of very good food at reasonable prices--and in a comfortable dining room. Also, nearby, Tia Sophia's is a casual place and a local favorite for great delicious New Mexican food. We ate what our waitress suggested, and she was right!

If you have the time, it is very worthwhile to visit Taos and the nearby Taos Pueblo.

HTTY

Either do a round trip as suggested by utahtea, or do one that centers on New Mexico (Albuquerque, Taos, Chaco Canyon, etc.) but includes southern Colorado (Mesa Verde, the Durango-Silverton train).

http://www.flickr.com/photos/mksfca/sets/72157622984070940/

http://www.flickr.com/photos/mksfca/sets/72157622636845987/show/with/4085893513/

The first two days are fine, but then you are only allowing one day to get to Colorado Springs and see the AFA, Pike's Peak, Garden of the Gods and the Royal Gorge ?... impossible in one day. It'll take at least 3 hours to get from RMNP/Estes to Colorado Springs and that's assuming you don't run into any traffic which is usually a problem on I-25. The Great Sand Dunes, Mesa Verde and the Colorado National Monument make for a very, very long trip. I'd cut at least one of them. New Mexico is really out of the question, but maybe you already realize that. My advice is to rethink and revise.

Rafting may not be possible or even advisible as the rivers may still be dangerous after all the snow we've experienced.

If you don't have any reservations for the holiday weekend, I'd get them ASAP.

We are not doing N. Mexico at all, just round trip from Denver and staying in Colorado the whole time. Out of the things in Colorado Springs, maybe we should skip Garden of the Gods? For the other choices, maybe we should pass on the National Monument. I am making all lodging reservations tonight so will be firming up our route and allowing more time with less attractions. Thank you all for feedback.