Are you thinking like an archaeologist? When do you think people made this? Who made this?
If you guessed that the Fox family did not build this you would be correct. This is a springbox built after the Fox family left. At one time this springbox helped provide a water supply to the dining room at Dickey Ridge Lodge, currently Dickey Ridge Visitor Center. Though the Fox family did not build this springbox, they did use the water here for their farming and other daily needs.
Opposed to the Fox family and many other mountain residents who lived in the hollows, the people building Shenandoah National Park in the 1930s wanted to highlight the views. So, Skyline Drive and all of the facilities and services for the Park followed the mountain ridge. The hollow homes, the lands cleared for grazing and farming, were eventually reforested and obscured from visitors' views. Yet visitors still needed running water, and the hollow provides that.