According to the United States Census Bureau, the town has a total area of 44.4 square miles (115.1 km2), all land.
[2] Glastenbury was first chartered in 1761 by New Hampshire Governor Benning Wentworth, but settlers did not begin trickling into this rocky, forbidding mountainous area for some years after.
These first settlers found life on Glastenbury Mountain difficult, as would residents ever after, and by 1800 they had been replaced by eight entirely different families.
Despite the many hardships that greeted Glastenbury settlers, newcomers continued to arrive in small numbers, and the population grew slowly to 76 in 1810.
Business interests in nearby Bennington were eager to take advantage of the vast timber resources there, and by 1872 had finally begun construction on a railroad (trolley) which ran up the mountain.
This includes only the enumerated population; there were many more transient workers who were drawn to the mountain to work in the then-booming logging business.
Dozens of kilns were built at South Glastenbury for converting the lumber to charcoal; at this time Glastenbury was one of the three foremost sites in Vermont for producing the charcoal which was feeding iron production in nearby Shaftsbury and in Troy, New York.
By the late 1880s, however, the mountain had been cleared of nearly all of its mature trees, and the town's economy dipped dramatically.
It was revived briefly in 1894 as an electric passenger trolley run by the Bennington & Woodford Railroad, and a brief and initially promising effort was made to convert South Glastenbury to a tourist attraction.