We've gone up in June a few times.  Some of the loops we rode would take around 8 hours.  There were also trails we turned around and came back on that took just as long.  Not sure how long it would take to follow those or where you would end up.  Each trail had spots that had me nervous enough to get down and lead my horse.  Might be due to being flat-landers or could have to do with riding a clumsy horse.  If you chose to turn around and ride back the way you came you can avoid some of those areas.

The scenery is awesome and you can spot bear, wolves, elk, deer, and moose.  There tends to be at least one moose that hangs out in the willows along the river where you would be crossing to pick up the trails.  We've been told we should be back on the camp side of the river by 3 as that's when the snow melt has brought up the river level and increased the flow enough to make crossing difficult.

The road in can be quite a journey.  There are a couple areas of switchbacks with fairly steep grades and loose rock.  I felt comfortable pulling a 22' box gooseneck but not sure I would have with anything larger.  We had rain and snow in mid-June and wouldn't recommend driving until the roads are dry.

There are some corrals near the river but we used a portable hot wire corral so the horses would have more room and be able to graze.  The friends we rode with used highlines at night as moose didn't respect or couldn't see their hot wire.

If I can answer any other questions or there are pics you'd like me to share of the Double Cabin area let me know. 

I created an album on here with a few pics.  If I did that right feel free to request other pics.  Didn't have pics of the corrals on this computer.

The camping area along the river with the corrals doesn't have shade trees.  There is shade from pines in the campground area and along the base of the mountains.  The corrals are out in the open.  The willow bushes are tall enough to hide moose, so there's shade from them for lawn chairs, etc.  Not sure how warm it would be in July, but in June I didn't feel a need to find shade.  I would ride in a t-shirt and by sunset have a winter coat on.   

When we rode out in the morning the river would be ankle to knee deep on the horses.  If we came back late afternoon there were spots it was up to their bellies.  I was more concerned with the current and rocks causing one to go down.  The dogs would end up quite a ways down stream by the time they swam to the other side.  I imagine the ranger is right that it wouldn't be an issue by July.  This past year we went the third week of June instead of the second and the river seemed lower. 

I'm not sure which trails we were on.  One did lead to a waterfall in the petrified forest area.  Seems we blazed our own trail to get that far.  One that does stand out was Bug Creek.  Most of that trail was switchbacks through the trees up to a cow camp with a small cabin and spring.  On the way back you have to cross the river and then follow a narrow trail up what seems like a vertical wall to us flat-landers.

Be prepared for a lot of fallen timber you will have to go around or over. 

I think the drive from Dubois to Double Cabin is around 20 miles, but it would take us around an hour to haul in.  Again, I would avoid driving on it when it's wet.  I would advise getting there early enough to still have daylight to haul in and set up camp.  Heading out from south central Nebraska on I80 to Rawlins, then Muddy Gap, Lander, Dubois and on to Double Cabin took around 14 hours.  Going there we drove as far as Sidney after work and stayed over at Cabelas.  They have corrals on the west side of the store.  I slept in the trailer next to them.  They have a hydrant right there and a place to dump shavings, etc.

Curious about your plans.  How many days will you be riding there?  Is everyone in the group experienced with mountain riding?  Do you know the route you're taking?  If you're avoiding I80 and driving in from the northeast part of Wyoming there are a couple of stop over places - Halsey Forest and Fort Robinson if you cut across Nebraska.     

I stopped over one night in Sidney NE.  There was a Motel just off the west exit to Sidney that has corrals. I don't remember how many pens. I think maybe 4.

Also the County Fairgrounds in Laramie WY have LOTS of stalls.  If there is not a rodeo or fair in town, There would be lots of available stalls.

I think they were $10 a night per stall.

We've only used the corrals at the Sidney Cabelas when we've taken the I80 route.  That's on the north side of the interstate exit.  There is a hotel on the south side as was mentioned that does have some corrals out back.  I can get the name/phone # from a friend that goes there each week.  The Kearney Cabelas has two corrals if something should happen to delay you. 

We didn't purchase certified hay.  We used certified Nebraska hay at Sidney.  At Double Cabin we let them graze in a hot wire pen that we moved daily and supplemented with grain and alfalfa cubes. 

Sounds like you're all seasoned veterans at mountain riding.  Each time I go I feel like a newbie.  On the drive home I think how lucky I was to have survived and not tumbled down the mountainside.  There's one thought that I'm sure you'll share with me.  You think about how awesome it is to be riding in an area that very few people will ever get to experience.

We've only stayed for a week but in that time we've taken different trails.  Some start off the same before branching, but the majority is different scenery.  We've also made our own trails on occasion.  I'd be interested in where you find the topo and quadrant maps to see if I could tell where we've been.  We had the luxury of riding with a guy that lives in Lander and spends his summers there so he knows the trails and (unfortunately) fears none of them.  Never bothered with GPS since we could rely on him or find a high spot to look down and find landmarks.  This past year we ran into some NOLS students on a trail.  That may be another source of information on the area and trails.   

Will be curious to see how your time estimates work out.  Where was your Teton ride in relation to Jackson Hole and Yellowstone?  I've hiked Jenny Lake and saw there are horse trails there.  Not  sure what to say about the trails as difficulty and obstacles are somewhat subjective.  Each trail we rode on had some obstacles.  There are ascents/descents with loose rock or solid rock faces.  Water crossings generally weren't a big deal.  We ran into a lot of downed trees.  Usually they were small enough to step over or in an area you could pick your way around the larger ones.  I didn't get the impression the Forest Service makes any effort to clear them.  There was evidence other riders cut through smaller trees that had lodged high enough they couldn't be stepped over.  Seems there were trail markers at intersections and spotty on the trails but the path was pretty easy to see.

Never carried a saw or axe on the trail but did buy a folding saw to take next year.  Doubt I'd spend much time cutting through a tree.  Figure I'd cut off the sharp places so the horses could jump it and not worry about getting cut.  One year riding at Fort Rob a wind storm knocked down a lot of dead trees from a previous fire.  A bulldozer had been used to clear a trail going uphill but it was a weekend so it had been parked part way up and left there.  A few of us would get off the horses, sit on the ground and use our legs to push the fallen trees over the edge.  It worked well and allowed us to continue our ride.  Always wonder what the guy running the bulldozer thought when he came back out and found the rest of the trail had already been cleared.

I'll try and post some more pics.  Wish there was an easy way to attach large ones to messages.  Not that pics do it justice.  I think you'll enjoy your time there.  

Added more pics to the album.  A couple show the corrals and surrounding area near the river.  One pic is of a waterfall - not sure if it's the one previously mentioned or not.  In the upper left of that shot there is a petrified tree stump. 

Haven't run into grizzly on horseback.  Grateful for that.  Doubt my paint would handle it well.  He will chase deer and dogs.  Will stand and watch moose, but is terrified of elk.  Hard to say what he would think of a bear.

I checked out those map/GPS links.  Pretty cool.  I have a GPS I take along each year, but never used it.  Should have marked the interesting spots with it and put them on the map.  Maybe in '08.

Hard to beat the area around Moran Junction, Jenny Lake and the Tetons, but I think you'll find this area comparable and special in its own way.

If my directions are right, that waterfall would be northwest of where the camping is.  Seems you would be riding towards Yellowstone to get there anyways.  There's a sign that lets you know you're headed towards the petrified forest.  I should have paid more attention to which trails were which.

If we make it back in '08, I will take along the GPS and mark the coordinates of things I find interesting so I can pass those along.  I would guess estimates on certain trails will be off quite a bit due to picking your way through all the downed timber.  My paint had a good time jumping them or stepping over with the front feet and then jumping with the back ones like a mule.  Some of the best Kodak moments were not captured as I was too concerned with the drop offs to get the camera out.

Another place to consider if some of your group doesn't have a LQ in the trailer, or you just want a night or two in a real bed.

www.alpinelakesandtrails.com

They rent out a small ranch.  You get a 3500 sf cabin, 10 beds, Kitchen, Hot showers etc Along with horse pasture for your horses.

It is in Dubois Wyoming and a short drive from lots of trail heads.