Park It and Stick It. Right Here. (1939)

Take a look at the back of any car and you will see that 8 out of 10 have some kind of sticker affixed to them. Candidates, pets, honor students and places visited in sticker form decorate vehicles old and new. In the 1920's with the growing interest in motoring and exploring, the National Park Service began to see more and more visitors at their gates.

As you paid your entrance fee you would be given a commemorative sticker like one of these to adorn your scrap book. Though I understand that instead people would stick them to their windshields and use them like they were park entrance passes.

With their appearance and popularity they came to be know as Zoo windshield stickers as each featured an animal along with the name of the park and were handed out from 12 different locations. Crater Lake (black bear), General Grant (Columbian gray squirrel), Glacier (mountain goat), Grand Canyon (beaver), Mesa Verde (coyote), Mt. Rainier (Columbian blacktailed deer), Rocky Mountain (big horn ram), Sequoia (the American elk or wapiti), Wind Cave (antelope), Yosemite (mountain lion) and Zion (porcupine), Yellowstone (Bison).

They eventually added more Parks, but there was some concern for public safety as collectors displayed these so much as to reduced the view through the windshield. The stickers were eventually reduced in size to the 2.25 inches you see above.

NPS Historic Photograph Collection

The stickers would be discontinued only a year after these were given out. To read more on the iconic items, take a look here.  

and while your at it - Visit Ranger Doug he has some neat reproduction items and good informaton about the way things used to be in our National Parks.