That’s the Commodore Hotel in 1919, with Grand Central Terminal on the left. The bridge in front connects the southern portion of Park Avenue to the elevated bypass around the terminal and then to the northern potion of the avenue. (The space under the bridge is called Pershing Square; the space on top of the bridge is most famous from the climactic battle at the end of The Avengers.)
The Commodore was not a great hotel*, but it was okay and being located next to Grand Central obviously helped business when everyone travelled long distance by train. As the picture shows, the outside was conventional and uninspired period-revival high-rise, although the ballroom and some other interior spaces were quite nice. The decline in train travel and a lack of upgrades led to the hotel’s demise in that form. It was heavily altered and reopened in 1980 as the Grand Hyatt.
Most of the old masonry curtain wall is still there, just covered by the glass. When you’re in a room, you see a traditional window, when you’re outside you see all glass…which is sort of backwards when you think about it. People inside would like the views, while the mirrored glass does nothing for 42nd Street.
In any case, the uglification of the building may have finally ended. Plans have been announced for its demolition. The driving factor is that it can be combined with some of the air-rights from Grand Central under the new Midtown East zoning, and the combined 2,000,000 square feet of space that could be built would allow for something very very large on this site.
I don’t know anyone who will be sad to see the Grand Hyatt go. And after 40 years, it’s hard to find people upset about the Commodore’s destruction outside of nostalgia. Grand Central deserves better as a neighbor.
* In the interests of full disclosure, I was one of the attendees at a Star Trek convention held at the Commodore in 1976.