http://daytoninmanhattan.blogspot.com/2010/06/vanderbilt-gates.html

Granted, the female in question is a young girl, but we still do see the occasional Shorpy picture from the 1900s where obviously mature women are wearing short(er) skirts.

For instance, the two women on the right, here:

https://www.shorpy.com/node/7880?size=_original#caption

It looks like hem length was more a matter of style and use than modesty; how else to explain the absolute ease with which women of the era wore bathing dress?

Maybe my tired old eyes are deceiving me but it looks to me as if the woman standing in the street with the cart is wearing a skirt whose length is more appropriate for a later era.

Maybe she's the 1905 version of a 1920's flapper.

[She and the chap both appear to be youngsters, which would make her skirt length appropriate for the time. -tterrace]

Thanks for the clarification, tterrace.

And here we are, on the cusp! By the time of this photo, with the center of New York commerce moving inexorably uptown and steel-framed skyscrapers beginning their proliferation, the land on which these magnificent buildings stood was already more valuable for commercial purposes than for residential. The generation that built these mansions usually stuck it out, but when they passed from the scene and multiple beneficiaries inherited, expediency demanded liquidation.

Concomitantly, and especially after World War I relaxed social divisions and occupational constraints, the availability of cheap staff to maintain such homes dwindled. While technological advances partially compensated for that social trend ("Look Cedric, I made toast!"), it nevertheless soon eventuated that only the richest of the rich could afford the huge staffs necessary to clean, maintain, and make comfortable such ostentatious lodgings.

While one certainly rues the loss of such architecture, it's worth considering that the economic and social trends that caused that loss are also the reason that more of us are not now scrubbing pots in some basement scullery.

And the fences (with their gates) are for what fences are always: to exclude those who do not belong (non-members of the Four Hundred) or, in other cases not depicted here, to keep those deprived of their liberty in.

By the time of the picture, Cornelius Vanderbilt II, had been dead for six years. His widow Alice still lived in the house, but no longer entertained. The boards might be up because she no longer needed the grand entrance for parties.

Also, since it's summertime, she was probably out at her other house, the Breakers in Newport, and had shut this house down for the summer - although boarding up the doors seems excessive.

The south entrance of the building at 58th street looks to be temporarily plywooded over. I didn't think it was available then . But it was developed in England in the 1860s and was common by the turn of the century . The 4 x 8 sheets standard today were not produced until 1928 . 1928 was also the year that this building and the 2 past it were replaced by the Bergdorf Goodman building.

Below is the same view from April of 2012.

Wonderful photo but what's with all the gates surrounding the buildings? Does anyone know?

[You mean the fences? -tterrace]

Sorry, correct.