Most of the photos on this site were extracted from reference images (high-resolution tiffs, 20 to 200 megabytes in size) from the Library of Congress research archive. (To query the database click here.) Many were digitized by LOC contractors using a Sinar studio back. They are adjusted by your webmaster for contrast and color in Photoshop before being downsized and turned into the jpegs you see here.
The year is 1912 and the place is Detroit. What's going on here? View full size.
UPDATE: Many people correctly identified this as the beginnings of a gas holder, or gasometer -- a storage reservoir for what used to be called "city gas," or coal gas (as opposed to the natural and LP gas that we use now). The original caption: "April 4, 1912. Foundation for gas holder, Detroit City Gas Company."