Whether you’re exploring the local area or hanging out at the campground, KOA Holidays are an ideal place to relax and play. There’s plenty to do, with amenities and services to make your stay memorable. Plus, you’ll enjoy the outdoor experience with upgraded RV Sites with KOA Patio® and Deluxe Cabins with full baths for camping in comfort. Bring your family, bring your friends, or bring the whole group – there’s plenty of ways to stay and explore.
Whether you’re exploring the local area or hanging out at the campground, KOA Holidays are an ideal place to relax and play. There’s plenty to do, with amenities and services to make your stay memorable. Plus, you’ll enjoy the outdoor experience with upgraded RV Sites with KOA Patio® and Deluxe Cabins with full baths for camping in comfort. Bring your family, bring your friends, or bring the whole group – there’s plenty of ways to stay and explore.
From Idaho Falls Idaho: Follow US-20 E to Island Park From Billings, MT: Follow I-90 W to Bozeman From Bozeman follow 191 South
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Every park calls itself big rig friendly, but make sure you mean it! Before you book a week outside the West Entrance, be sure you check site length, pull-through access, power and the road in. Island Park KOA Holiday answers all four.
Long enough for the rig you actually drive. That may not match the spec sheet.
Get out a tape and measure bumper to bumper. Count the ladder, the spare tire mount and anything you bolted on later, like a bike rack or cargo carrier, because add-ons don't show up in the factory length. Then there's the truck or toad. You might stay hitched for a one-nighter, but for a few days at a Yellowstone base camp you'll unhook, and that second vehicle needs a place to sit.
A posted max length only tells you the biggest rig a park will take. It says nothing about which sites can hold it. So pay attention to site type.
Island Park KOA Holiday takes RVs up to 50 feet. The Premium XL pull-through sites are built for big rigs and include parking for one vehicle in addition to your RV. Long rig or towing? Book Premium XL. Put your exact length and slide-out count into the reservation so you end up on a site that fits.
If you flat-tow a car behind a Class A, a pull-through saves you a lot of hassle. Most towed cars can't be backed up while still hooked to the coach without risking the tow bar or the car's steering. On a back-in site you unhook on the park road, back the coach in, then go find somewhere to put the car. Maybe with someone waiting behind you.
Fifth wheels have more room to work with. Still, after six hours on the interstate, pulling straight in beats backing 45 feet of trailer into a gap between two pedestals.
Plenty of people back in without thinking twice. If you'd rather not, Island Park KOA's Premium XL sites are pull-throughs. You drive in and you're parked.
Thirty amps gets you about 3,600 watts. Fifty amps gets you two 120-volt legs at 50 amps each, roughly 12,000 watts. That's more than three times the power, and a lot of newer Class A coaches and fifth wheels are wired with that in mind.
Try running two roof ACs on 30 amps. Add a residential fridge or an induction cooktop and you're choosing which appliance gets to run.
Island Park sits around 6,500 feet up, and generators lose output at elevation. If you were planning to make up the difference with a generator, keep that in mind.
Premium XL pull-through sites at Island Park KOA have 20, 30 and 50-amp service. At any park, plug a surge protector or EMS into the pedestal before you plug in the rig, and keep a 50-to-30 adapter in a bay in case one outlet is down. Look over your shore cord plug for scorch marks or loose prongs before you leave home.
Full hookups means water, sewer and electric at the site. You can live without sewer for a weekend. Over five or seven nights near Yellowstone, two people showering every day will fill a gray tank fast, and nobody wants to spend vacation time in the dump station line.
Getting to the site matters as much as what's on it. Phone GPS doesn't know how tall you are. A shortcut that looks fine on a map can put a 13-foot coach on a narrow road with nowhere to turn around.
Island Park KOA is right off US-20, the main highway between Idaho Falls and West Yellowstone. Exit the highway and you're there. There's a gas station, convenience store, camp store, propane fill, laundromat and a KampK9 dog park on-site, so you're not unhooking the truck every time you run out of milk.
About 25 minutes. Head north on US-20 through West Yellowstone to the West Entrance of Yellowstone National Park, the most direct way to Old Faithful, Grand Prismatic Spring and the Madison River.
Leave the RV plugged in at camp and take the tow vehicle into the park. A pickup or a Jeep is a lot easier to park at a trailhead than a 45-foot coach.
Give yourself a day off from the park, too. Big Springs, the headwaters of the Henry's Fork, is close by. So is Henry's Lake. Upper and Lower Mesa Falls are a short drive south, and from Sawtelle Peak you can look across into Yellowstone and the Caribou-Targhee National Forest.
Island Park KOA is a seasonal campground. Mid-June through Labor Day is peak season, which is when the site you want is hardest to get. Book summer dates early.
Have your measurements handy before you start.
Still comparing parks along this stretch? Our guide to choosing a basecamp near Yellowstone's West Entrance covers the options.
Island Park KOA Holiday takes RVs up to 50 feet. If you're on the long end or towing a car, book a Premium XL pull-through site. They're built for big rigs and include parking for one vehicle in addition to your RV, so your truck or toad stays with you.
Yes. The Premium XL pull-through sites have 20, 30 and 50-amp service. If your rig is wired for 50 amps, which is common on coaches running two roof air conditioners, book Premium XL and bring a surge protector for the pedestal.
Yes. The Premium XL sites are pull-throughs with 20/30/50-amp service and parking for one extra vehicle. A Class A towing a car can pull in without unhooking or backing up, and fifth-wheel owners can stay hitched for a quick overnight.
About 25 minutes. Drive north on US-20 through West Yellowstone, Montana, to the park's West Entrance, the most direct route to Old Faithful and Grand Prismatic Spring. With a big rig, it's easier to leave the RV hooked up at camp and take the tow vehicle into the park.
Long rig, towed car or a 50-amp setup? Premium XL is your site, and summer is peak season, so book early. Reserve your Premium XL site at Island Park KOA Holiday.
That doesn't mean this area has to always be empty. When you start reviewing camping options, your history will display here to help compare sites and find the best stay. You will be able to share your stay information with friends or family and save it for a later time if you have a KOA Account.
Make checkout easy by booking all your reservations at once. Add your sites from different campgrounds into your shopping cart* and then choose checkout.
