I roto i te 1918, ka kauwhautia e te Perehitini Woodrow Wilson a Katmai National Monument i Alaska, neke atu i te 1,000,000 eka (4,000 km2). I whakarahihia a Katmai ki te tata ki te 2,800,000 eka (11,000 km2) na nga panui o te Ture Antiquities Act i muri mai, a he maha nga tau ko te waahanga nui rawa o te punaha papa whenua. Ko Petrified Forest, Grand Canyon, me Great Sand Dunes i kiia ano he tohu whenua, a ka tohua hei papa whenua e te Kaunihera. Hei whakautu ki te whakapuaki a Roosevelt mo te tohu nui o Grand Canyon, i whakawakia e tetahi kaitono keri i te kooti federal, e kii ana kua takahi a Roosevelt i te mana o te Ture Antiquities Act ma te tiaki i tetahi awa katoa. I te tau 1920, i whakatau te Kooti Nui o Amerika i te Kotahitanga o te Grand Canyon he "kaupapa putaiao, he taonga hitori ranei" ka taea te tiaki ma te panui, te whakarite i te ture mo te whakamahi motuhake o te Ture Antiquities Act.
Ko Woodrow Wilson