National Park - Badlands National Park, SD, U.S.A

• Size: XL

• Sim Rating: ⭐⭐⭐ (General Aviation)

• Verdict: The "eroded buttes" usually rely on satellite imagery. From 1,000ft they look incredible, but if you fly too low, the sharp ridges look "melted" or soft.

• Description: The park covers 242,756 acres and includes dramatic rock formations, eroded buttes, pinnacles, and spires - it has the largest undisturbed mixed-grass prairies in the country.
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National Park - Canyonlands National Park, UT, U.S.A

• Size: XL

• Sim Rating: ⭐⭐⭐⭐ (Bush Plane)

• Verdict: The massive mesas hold their shape well in sims, but the intricate "Needles" area can look flat without custom 3D scenery add-ons.

• Description: The park covers 337,598 acres and is divided into four distinct districts: Island in the Sky, The Needles, The Maze, and the rivers themselves - Includes a massive mesa & colourful rock spires.
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National Park - Crater Lake National Park, OR, U.S.A

• Size: L

• Sim Rating: ⭐⭐ (Bush Plane)

• Verdict: The rim and the water mask are usually very sharp, but Wizard Island can sometimes look a bit generic close up.

• Description: The park covers 183,224 acres and includes stunning landscapes, including volcanic formations, forests - Crater Lake is deepest lake in the United States.
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National Park - Death Valley National Park, CA, U.S.A

• Size: XXL

• Sim Rating: ⭐⭐⭐ (General Aviation)

• Verdict: Because it is so vast and flat, the textures can get blurry low down. The salt flats look great from high up, but lack texture on the ground.

• Description: The park covers 3.4 million acres and includes stunning landscapes, including salt flats, sand dunes, badlands, valleys, canyons, and towering mountains - Badwater Basin sits at 282 feet (86 meters) below sea level.
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National Park - Glacier National Park, MT, U.S.A

• Size: XXL

• Sim Rating: ⭐⭐⭐⭐ (Bush Plane)

• Verdict: The elevation mesh (shape of mountains) here is usually top-tier, making for epic valley flying.

• Description: The park covers over one million acres - Stunning Glacier carved Mountains & gorgeous Alpine scenery.
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National Park - Grand Canyon National Park, AZ, U.S.A

• Size: XXL

• Sim Rating: ⭐⭐⭐⭐⭐ (Helicopter Ready)

• Verdict: The gold standard of flight sim scenery. High-resolution data usually allows you to fly inside the canyon below the rim with high fidelity.

• Description: Covers 1,218,375 acres in exceptional detail - Lots of POI's.
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National Park - Grand Teton National Park, WY, U.S.A

• Size: XL

• Sim Rating: ⭐⭐⭐⭐ (Bush Plane)

• Verdict: The mountains look photo-real from the cockpit, though the lakes sometimes have shoreline issues.

• Description: The Park covers 310,000 acres and includes beautiful Mountains, stunning lakes - home of the Teton Range, including Grand Teton, it's tallest peak.
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National Park - Great Smoky Mountains National Park, TN, U.S.A

• Size: L

• Sim Rating: ⭐⭐⭐ (General Aviation)

• Verdict: This is a "tree heavy" park. Unless you have seasonal mods, it can look like an endless carpet of generic green trees.

• Description: Part of the Appalachian Mountains known for their smoke like fog - Covers 187,000 acres of Forest - Kuwohi is its highest peak.
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National Park - Joshua Tree National Park, CA, U.S.A

• Size: XL

• Sim Rating: ⭐⭐ (High Altitude)

• Verdict: Very difficult for sims to render. The iconic Joshua Trees are often missing (replaced by generic bushes) or appear as 2D flat images.

• Description: The park covers an area of 795,156 acres and includes unique rock formations, vast wilderness, and iconic Joshua trees - A stunning desert landscape.
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National Park - Kings Canyon National Park, CA, U.S.A

• Size: XL

• Sim Rating: ⭐⭐⭐ (General Aviation)

• Verdict: Deep canyons look great, but the Sequoia trees are often not rendered at their true massive size in default sims.

• Description: The park covers an massive 461,901 acres and includes deep canyons, huge sequoia trees and the General Grant Tree.
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National Park - Lassen Volcanic National Park, CA, U.S.A

• Size: L

• Sim Rating: ⭐⭐⭐⭐ (Bush Plane)

• Verdict: Volcanic landscapes usually have distinct colors that satellite imagery picks up well.

• Description: The park covers 106,452 acres and includes Lassen Peak, Hydrothermal Features, Painted Dunes & four types of volcanoes.
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National Park - Marble Canyon, AZ, U.S.A

• Size: XL

• Sim Rating: ⭐⭐⭐⭐ (Bush Plane)

• Verdict: Similar to the Grand Canyon but often slightly lower resolution on the cliff faces.

• Description: Marks the beginning of the Grand Canyon - Includes Navajo Bridge & Vermilion Cliffs stunning red rock formations.
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National Park - Mesa Verde National Park, CO, U.S.A

• Size: M

• Sim Rating: ⭐⭐ (High Altitude)

• Verdict: The famous "Cliff Dwellings" are almost always flat textures on the wall. You cannot fly into the caves; they look painted on.

• Description: The Park covers over 52,000 acres - With its well preserved Ancestral Puebloan cliff dwellings & includes Cliff Palace as a POI.
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National Park - Mount Rainier National Park, WA, U.S.A

• Size: XL

• Sim Rating: ⭐⭐⭐⭐⭐ (Helicopter Ready)

• Verdict: Usually a "star" of the simulator. The massive standalone mountain has incredible custom mesh and texture details.

• Description: The park covers 236,381 acres and includes Mt Rainier a stratovolcano that is 14,410 feet tall - Huge glacial system with stunning scenery.
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Tribal Park - Monument Valley, AZ, U.S.A

• Size: XL

• Sim Rating: ⭐⭐⭐⭐⭐ (Helicopter Ready)

• Verdict: Iconic. Most modern sims give this "hero" treatment with custom 3D models for the Mittens that you can fly around.

• Description: Part of the Navajo Nation it's a tribal park - Includes the Mittens & Merrick Butte, John Ford’s Point, Totem Pole & Yei Bi Chei.
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National Park - North Cascades National Park, WA, U.S.A

• Size: XL

• Sim Rating: ⭐⭐⭐⭐ (Bush Plane)

• Verdict: The "American Alps" are jagged and dramatic, looking fantastic from the cockpit of a cub, even if snow textures can sometimes look repetitive.

• Description: The park covers over 500,000 acres and includes over 300 glaciers, deep valleys and jagged peaks - also know as the American Alps.
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National Park - Olympic National Park, WA, U.S.A

• Size: XXL

• Sim Rating: ⭐⭐⭐ (General Aviation)

• Verdict: A mix of everything. The mountains are great, but the rainforests are often just dense generic trees.

• Description: The park covers nearly 1 million acres and includes glacier-capped mountains, temperate rainforests with stunning views all around.
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National Park - Rocky Mountains National Park, CO, U.S.A

• Size: XL

• Sim Rating: ⭐⭐⭐⭐ (Bush Plane)

• Verdict: High elevation flying at its best. Trail Ridge Road is a great visual guide to follow from the air.

• Description: Includes Bear Lake, Longs Peak & Trail Ridge Road and covers 415 square miles of breath taking scenery - Close to Denver, Colorado.
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National Park - Sequoia National Park, CA, U.S.A

• Size: XL

• Sim Rating: ⭐⭐⭐ (General Aviation)

• Verdict: Similar to Kings Canyon—great terrain shape, but the specific "Giant" trees are rarely modeled individually, making it look like a standard forest.

• Description: This Park covers over 400,000 acres and is home to the giant Sequoia trees inc. the General Sherman Tree - Mount Whitney is it's highest peak.
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National Park - Theodore Roosevelt National Park, ND, U.S.A

• Size: M

• Sim Rating: ⭐⭐⭐ (General Aviation)

• Verdict: Beautiful rolling prairies, but lacks the dramatic verticality that makes for "wow" moments in a flight sim.

• Description: The park covers 70,446 acres and includes rugged Badlands & rolling prairies - The Little Missouri River winds through the park offering stunning views.
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National Park - Yellowstone National Park, WY, U.S.A

• Size: XXL

• Sim Rating: ⭐⭐⭐⭐ (Bush Plane)

• Verdict: The Grand Prismatic Spring looks incredible from the air (great colors), but Old Faithful is usually just a flat patch of ground unless you have visual effects mods.

• Description: At 2.2 million acres across Wyoming, Montana, and Idaho it includes the Old Faithful geyser & Grand Prismatic Spring.
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National Park - Yosemite National Park, CA, U.S.A

• Size: XL

• Sim Rating: ⭐⭐⭐⭐⭐ (Helicopter Ready)

• Verdict: A masterpiece of verticality. El Capitan and Half Dome are usually custom modeled, allowing for thrilling proximity flying.

• Description: The park covers 759,620 acres and includes Glacier Point, El Capitan, Yosemite Falls, Tioga Pass & High Sierra.
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Credit to @SlabsFly for the brilliant idea to rate this list!