Photographed over forty years (1969-2008) by architectural critic and curator John Margolies, the collection consists of 11,710 color slides of roadside attractions, gas stations, pumps, etc

https://blogs.loc.gov/loc/2017/07/free-to-use-and-reuse-john-margolies-photographs-of-roadside-america/

this was at 8th and Market in San Diego, 1977

Starting in the 1970s, he spent much of his life scouring back roads for those vanishing emblems of midcentury enterprise, which were already imperiled by air travel, interstates and big-box sprawl.

After studying at the University of Pennsylvania, from which he earned a bachelor’s degree in art history and journalism and a master’s in communications, Mr. Margolies became an editor at Architectural Record magazine. He also served as program director at the Architectural League of New York.

you can look through them here: https://www.loc.gov/pictures/search/?q=mrg&st=gallery

The 35 mm slides were digitized in 2016 and are available online. The digital images are used in preference to the original slides, which are kept in cold storage to preserve them.

If you've been reading along on my blog for a couple years these will be familiar

Margolies' Roadside America work chronicled a period of American history defined by the automobile and the ease of travel it allowed. Emerging with the prosperity of the post-WWII era, roadside and commercial structures spread with the boom of suburbanization and the expansion of paved roads across the United States. Yet, in many instances, the only remaining record of these buildings is on Margolies' film, because tourist architecture was endangered by the expansion of the interstate system and changing travel desires. Margolies' work was influential in the addition of roadside buildings to the National Register of Historic Places beginning in the late 1970s.

His travels were variously underwritten by a Guggenheim Foundation grant and the architect Philip Johnson ( a favorite of mine ), he spent as many as eight weeks at a stretch in pursuit of obscure roadside attractions.

https://www.loc.gov/pictures/search/?q=mrg&sp=3&st=gallery  as you can see, 586 pages, 20 per page, that's 11612 images, roughly

https://www.loc.gov/free-to-use/john-margolies-roadside-america-photograph-archive/


His books include
 “Pump and Circumstance: Glory Days of the Gas Station” (1993);
“Home Away From Home: Motels in America” (1995);
 “Fun Along the Road: American Tourist Attractions” (1998).
The End of the Road: Vanishing Highway Architecture in America. New York: Penguin 1981.
Miniature Golf (Abbeville Press, 1987).
Resorts of the Catskills (St. Martin's Press, 1979).
Roadside America: Architectural Relics from a Vanishing Past,  Taschen, 2010.
See the USA: The Art of the American Travel Brochure (Chronicle Books, 2000).
Signs of Our Time (Abbeville Press, 1993).
Ticket to Paradise: American Movie Theaters and How We Had Fun (Bulfinch Press, 1991).

Margolies normally rented a car and embarked in the late spring or after Labor Day, when the families and tourists were not crowding the roads. He packed coolers for keeping the film cool.

Most nights, he stayed in motels, which he documented in Home Away From Home: Motels in America (1995). He always brought clothespins to secure the drapes

He preferred to photograph early mornings with cloudless, blue skies and would skip sites if the light wasn't right or if cars blocked the scene. As he stated in Roadside America, "I love the light at that time of day; it's like golden syrup. Everything is fresh and no one is there to bother you."

Margolies' photography and writing contributed to shaping the postmodernist movement. In 1978, Margolies was awarded a Guggenheim Fellowship. He was also supported by the Howard Gilman Foundation, the National Endowment for the Arts, and the Wyeth Endowment for American Art. In 2003, he was named Josephine Patterson Albright Fellow by the Alicia Patterson Foundation.

https://www.nytimes.com/2016/06/03/arts/john-margolies-photographer-of-whimsical-architecture-dies-at-76.html?_r=1
https://www.thegentlemanracer.com/2020/06/the-art-of-gas-pump.html
https://www.loc.gov/rr/print/coll/john-margolies-roadside-america-photograph-archive.html