How big are the national parks?

May 29, 2019

For the next few posts I will concentrate on the 61 units with the designation “national park.” These are the crown jewels of the system and certainly get the most press — check out Ken Burns’ documentary “The National Parks: America’s Best Idea,” watched by over 30 million people in its first run on PBS in 2009.

How big are these national parks? Are they millions of acres? Hundreds? Are they all relatively the same size or are there some outliers? How big does a park have to be to keep the park in it’s natural state? That last one is a hard question to answer and has caused some headaches for the National Park Service over the years.

The map below shows the size of all the national parks with a circle relative to each park’s area (not the actual park boundary).

An interactive version of the map that will tell you the park name and size in acres and square miles when you hover over a circle is found here.

Map image The map was created using the Python library, Folium

The largest national park is Wrangell-St. Elias in Alaska at 8.3 million acres (13,004 square miles), and the smallest is Gateway Arch in Missouri at 193 acres (.3 square miles).* Those Alaska parks are huge! Seven of the top 10 largest parks are in Alaska. The largest park in the lower 48 is Death Valley National Park in California, number 5 overall, at 3.4 million acres (5,270 square miles).

*Gateway Arch National Park protects a manmade object built in the 1960s, and while a notable historic object, its being designated a national park perhaps does not fulfill the mission of such a designation, which is meant to protect areas of natural signifigance. Not everyone agreed with the designation of the arch as a national park in 2018.

The average (mean) national park size is ~856,000 acres (1,338 square miles) and the median is ~221,000 acres (346 square miles). Because the median is so much smaller than the mean, we can tell that the data is skewed to the right, or exhibits positive skew. Let’s take a look at this in a histogram of the data.

Histogram image

We can see that 49 of the national parks are smaller than one million acres. The top 12 are greater than one million with two real outliers in Alaska over 7.5 million. Those big parks are very big but most of the national parks lie in a more narrow range.

National Parks in Order of Size

Park Name Size (acres) Size (square miles)
1 Wrangell-St. Elias National Park 8,323,146 13,005
2 Gates of the Arctic National Park 7,523,897 11,756
3 Denali National Park 4,740,911 7,408
4 Katmai National Park 3,674,529 5,741
5 Death Valley National Park 3,372,981 5,270
6 Glacier Bay National Park 3,223,383 5,037
7 Lake Clark National Park 2,619,816 4,093
8 Yellowstone National Park 2,219,791 3,468
9 Kobuk Valley National Park 1,750,716 2,735
10 Everglades National Park 1,508,939 2,358
11 Grand Canyon National Park 1,201,647 1,878
12 Glacier National Park 1,013,126 1,583
13 Olympic National Park 922,649 1,442
14 Big Bend National Park 801,163 1,252
15 Joshua Tree National Park 790,636 1,235
16 Yosemite National Park 761,748 1,190
17 Kenai Fjords National Park 669,650 1,046
18 Isle Royale National Park 571,790 893
19 Great Smoky Mountains National Park 522,427 816
20 North Cascades National Park 504,781 789
21 Kings Canyon National Park 461,901 722
22 Sequoia National Park 404,063 631
23 Canyonlands National Park 337,598 527
24 Hawai'i Volcanoes National Park 325,605 509
25 Grand Teton National Park 310,044 484
26 Rocky Mountain National Park 265,807 415
27 Channel Islands National Park 249,561 390
28 Badlands National Park 242,756 379
29 Capitol Reef National Park 241,904 378
30 Mount Rainier National Park 236,382 369
31 Petrified Forest National Park 221,390 346
32 Voyageurs National Park 218,200 341
33 Shenandoah National Park 199,224 311
34 Crater Lake National Park 183,224 286
35 Biscayne National Park 172,971 270
36 Zion National Park 147,243 230
37 Redwood National Park 138,999 217
38 Great Sand Dunes National Park 107,342 168
39 Lassen Volcanic National Park 106,589 167
40 Saguaro National Park 91,716 143
41 Guadalupe Mountains National Park 86,367 135
42 Great Basin National Park 77,180 121
43 Arches National Park 76,679 120
44 Theodore Roosevelt National Park 70,447 110
45 Dry Tortugas National Park 64,701 101
46 Mammoth Cave National Park 54,012 84
47 Mesa Verde National Park 52,485 82
48 Acadia National Park 49,075 77
49 Carlsbad Caverns National Park 46,766 73
50 Bryce Canyon National Park 35,835 56
51 Wind Cave National Park 33,971 53
52 Haleakalā National Park 33,265 52
53 Cuyahoga Valley National Park 32,572 51
54 Black Canyon of the Gunnison National Park 30,780 48
55 Pinnacles National Park 26,686 42
56 Congaree National Park 26,640 42
57 Indiana Dunes National Park 15,348 24
58 Virgin Islands National Park 14,945 23
59 National Park of American Samoa 8,257 13
60 Hot Springs National Park 5,552 9
61 Gateway Arch National Park 193 <1

Data Sources

The list of 419 official park units (as of 5/1/2019) broken out by designation comes from the National Park System page at nps.gov. Park location data, including latitude, longitude, and state(s) are from the National Park Service API. Park size data is from the report, “Park Acreage Reports (1997 – Last Calendar/Fiscal Year)” found on the NPS Stats website.

Using the Scripts

Instructions to run the scripts are found in the readme in the GitHub repository found here.


Written on May 29, 2019