Glentanner Park Centre has all sorts of accommodation options, from cozy units to campervan and tent sites. Plus, they're the hub for epic activities like helicopter flights, glacier trips, and mountain biking. It's a great option when the Whitehorse Hill Campground is full but you still want to be close to the national park.
NOTE: There is NO DUMP STATION at this campground neither anywhere inside Mount Cook National Park. Make sure to dump your grey water tank back in Twizel or Lake Tekapo before heading to this area!