1: The Republic of Biscayne NP
Pop: 4,009 Mil

2: The Republic of Isle Royale NP
Pop: 4,001 Mil

3: The Republic of Channel Islands NP
Pop: 3,998 Mil

4: The Republic of Great Sand Dunes NP
Pop: 3,998 Mil

5: The Republic of Sequoia NP
Pop: 3,998 Mil

6: The Republic of Dry Tortugas NP
Pop: 3,994 Mil

7: The Republic of Mount Rainier NP
Pop: 3,994 Mil

8: The Republic of Everglades NP
Pop: 3,991 Mil

9: The Republic of Mesa Verde NP
Pop: 3,991 Mil

10: The Republic of Haleakala NP
Pop: 3,990 Mil

11: The Republic of Zion NP
Pop: 3,989 Mil

12: The Republic of Gates of the Arctic NP
Pop: 3,988 Mil

13: The Republic of Great Smoky Mountains NP
Pop: 3,988 Mil

14: The Republic of North Cascades NP
Pop: 3,988 Mil

15: The Republic of Grand Canyon NP
Pop: 3,985 Mil

16: The Republic of Olympic NP
Pop: 3,985 Mil

17: The Republic of Wind Cave NP
Pop: 3,984 Mil

18: The Republic of Indiana Dunes NP
Pop: 3,984 Mil

19: The Republic of Hot Springs NP
Pop: 3,982 Mil

20: The Republic of Joshua Tree NP
Pop: 3,982 Mil

21: The Republic of Redwood NP
Pop: 3,982 Mil

22: The Republic of Canyonlands NP
Pop: 3,980 Mil

23: The Republic of Hawaii Volcanoes NP
Pop: 3,979 Mil

24: The Republic of Lassen Volcanic NP
Pop: 3,978 Mil

25: The Republic of Yellowstone NP-
Pop: 3,977 Mil

26: The Republic of Kenai Fjords NP
Pop: 3,976 Mil

27: The Republic of Congaree NP
Pop: 3,975 Mil

28: The Republic of Great Basin NP
Pop: 3,975 Mil

29: The Republic of Denali NP
Pop: 3,972 Mil

30: The Republic of Big Bend NP
Pop: 3,970 Mil

31: The Republic of Grand Teton NP
Pop: 3,969 Mil

32: The Republic of Crater Lake NP
Pop: 3,968 Mil

33: The Republic of Death Valley NP
Pop: 3,968 Mil

34: The Republic of Gateway Arch NP
Pop: 3,967 Mil

35: The Republic of Saguaro NP
Pop: 3,967 Mil

36: The Republic of Black Canyon of the Gunnison NP
Pop: 3,964 Mil

37: The Republic of Virgin Islands NP
Pop: 3,964 Mil

38: The Republic of Arches NP
Pop: 3,962 Mil

39: The Republic of Capitol Reef NP
Pop: 3,962 Mil

40: The Republic of Katmai NP
Pop: 3,962 Mil

41: The Republic of Guadalupe Mountains NP
Pop: 3,961 Mil

42: The Republic of Petrified Forest NP
Pop: 3,961 Mil

43: The Republic of Badlands NP
Pop: 3,960 Mil

44: The Republic of Wrangell St Elias NP
Pop: 3,958 Mil

45: The Republic of New River Gorge NP
Pop: 3,958 Mil

46: The Republic of Rocky Mountain NP
Pop: 3,957 Mil

47: The Republic of White Sands NP
Pop: 3,957 Mil

48: The Republic of American Samoa NP
Pop: 3,953 Mil

49: The Republic of Lake Clark NP
Pop: 3,953 Mil

50: The Republic of Pinnacles NP
Pop: 3,953 Mil

51: The Republic of Carlsbad Caverns NP
Pop: 3,952 Mil

52: The Republic of Theodore Roosevelt NP
Pop: 3,952 Mil

53: The Republic of Mammoth Cave NP
Pop: 3,951 Mil

54: The Republic of Shenandoah NP
Pop: 3,951 Mil

55: The Republic of Voyageurs NP
Pop: 3,951 Mil

56: The Republic of Kobuk Valley NP
Pop: 3,949 Mil

57: The Republic of Yosemite NP
Pop: 3,947 Mil

58: The Republic of Glacier Bay NP
Pop: 3,946 Mil

59: The Republic of Bryce Canyon NP
Pop: 3,944 Mil

60: The Republic of Cuyahoga Valley NP
Pop: 3,943 Mil

61: The Republic of Kings Canyon NP
Pop: 3,941 Mil

62: The Republic of Acadia NP
Pop: 3,940 Mil

63: The Republic of Glacier NP
Pop: 3,928 Mil