Good question! I guess most "new" arches start out as small and relatively unspectacular "windows", then grow over thousands or millions of years and finally co

Good question! I guess most "new" arches start out as small and relatively unspectacular "windows", then grow over thousands or millions of years and finally collapse. So when a new arch forms, it doesn't turn into a tourist attraction right away. The place with probably the highest density of arches in the world, Arches National Park, doesn't even seem to be sure how many arches it has. Their homepage says "over 2000", while the article https://www.nps.gov/parkhistory/online_books/geology/publications/bul/1393/sec8.htm https://www.nps.gov/parkhistory/online_books/geology/publica... has a much more conservative estimate of 124...