My god, it's full of stars!
This old postcard features the Milky Way, as someone has conveniently written in ink across the top. Specifically, it's the Milky Way near Rho Ophiuchi.
This postcard, never used, is from the Adler Planetarium and Astronomical Museum in Chicago, which opened in 1930. The image itself is quite a bit older than that, according to the text on the back of the postcard:
"The nebulous matter overlying this region is in part illuminated by the enmeshed stars and in part remains dark, recognized only by obscuration of the stars of the background. The dark lanes extend far beyond the limits of this picture. Photograph by Barnard, 5 April 1905. Exposure 4.5 hours Bruce telescope temporarily at Mt. Wilson."Barnard refers to astronomer E.E. Barnard (1857-1923), while "Bruce telescope" likely refers to the 24-inch Bruce Doublet, which was first installed at Harvard University in 1893. You can read more about it here.
One of my bucket-list items is to get a good view of the Milky Way with the naked eye. My best bet is probably Cherry Springs State Park, in Potter County, northcentral Pennsylvania.