The town takes its name from Admiral Sir Peter Warren.

[4] From 1909 until 1970, Glencliff, located in the northern part of Warren, was the mailing address for the New Hampshire State Sanatorium, located just over the town line in Benton, at an elevation of 1,650 feet (500 m) on the slopes of Mount Moosilauke.

Before the discovery of antibiotics, pure mountain air was thought to be curative for patients with tuberculosis.

With its own farm on 500 acres (200 ha), the facility treated more than 4,000 individuals over its first half century, admitting between 50 and 100 per year.

[5] The town's most famous landmark is a Redstone ballistic missile erected in the center of the village green.

It was donated by Henry T. Asselin, who transported the missile from the Redstone Arsenal near Huntsville, Alabama, in 1971, then placed it in honor of long-time Senator Norris Cotton, a Warren native.

The highest point in Warren is at the southern boundary of the town, on the north ridge of Carr Mountain, where the elevation reaches approximately 3,330 feet (1,010 m) above sea level.