I took a solo trip for 7 days and 6 nights to Yellowstone and Grand Teton and it was my first time to either park. I flew into Billings and rented a car for the entire duration (Hyundai Sportage SUV). Thanks to everyone who provided their advice/comments prior to me leaving!
Link to a very long trip report with some photos: http://txpdtravel.blogspot.com
Sat., June 15 – Land in Billings in the morning. Drive Beartooth Highway to Yellowstone. Hike the Yellowstone River Picnic Trail, Lost Creek Falls, and Hellroaring Trail (to the suspension bridge). Stay at Roosevelt Roughrider Cabin (1 Double with a shared bath).
Sun., June 16 – Visit Sulphur Caldron, Mud Volcano, Artist Point, Brink of Upper Falls, Brink of Lower Falls, Lookout Point, Grand View and Inspiration Point. Hike the Lamar River Trail, Trout Lake, Tower Fall, and Chittenden Trail of Mt. Washburn. Stay at Canyon Frontier Cabin (1 Queen with bathroom).
Mon., June 17 – Visit Artist Point, Uncle Tom’s Trail/Point, Upper Falls View, West Thumb Geyser Basin, Lewis Falls, Moose Falls, Oxbow Bend. Hike the Pelican Creek Trail and Elephant Back Trail near Fishing Bridge. Stay in Grand Teton at Signal Mountain Lodge Rustic Cabin (1 Double with bathroom and fireplace).
Tue., June 18 – Visit Oxbow Bend, Mormon Row, Kepler Cascades, Black Sand Basin, Firehole Lake Drive, Lower Geyser Basin/Fountain Paint Pot, Midway Geyser Basin, and Biscuit Basin. Hike Schwabacher Landing and Hidden Falls/Inspiration Point/Cascade Canyon. Stay at Old Faithful Inn Old House Room (1 Queen with a shared bath).
Thu., June 20 – Visit Terrace Spring, Gibbon Falls, Artist Paintpots, Norris Geyser Basin, Roaring Mountain, Sheepeater Cliff, Golden Gate, Mammoth Upper Terrace Drive, and Mammoth Lower Terrace. Hike Ice Lake Trail and Beaver Pond Loop. Stay at Mammoth Springs Frontier Cabin (2 Queens with bathroom).
Wildlife Sightings – Red Fox, Bison (and calves), Pronghorn, Bighorn Sheep, Black Bear (and cubs), Grey Wolf, Mule Deer, Elk (and calves), Mountain Goat, Osprey, Muskrat, Marmot, Snowshoe Hare, Great Blue Heron, Canada Geese, Sandhill Crane, Mountain Bluebird, Dusky Grouse, Golden-Mantled Ground Squirrel, Uinta Ground Squirrel, Mallard Ducks, Cliff Swallows. other birds/ducks that I couldn't identify.