When we call ahead for reservations, we always give our rig length of 36 feet, not including the truck. My guess is that we are not alone finding that some of the campgrounds will put us in sites that are barely long enough for the trailer. We also always inform them that we have slides as some sites are quite narrow. If we are travelling and only plan to stay one night in a campground, we will often ask for a pull-thru long enough to accommodate our total "hooked-up" length to make our morning departure easier. Sometimes you get what you want...sometimes not exactly. Only once did we get to a campground that assured us they could accommodate our length to find that we couldn't even turn off the highway into the drive due to overhanging tree branches. Height, for us, is a bigger concern than length.