Dictionary descriptions of “untrammeled” include “unrestrained,” “unrestricted,” “unimpeded,” and “unfettered.” Remaining untrammeled from intentional human manipulation is what keeps Wilderness wild.

The first sentence in Section 2(c) of the Wilderness Act defines Wilderness:
“A wilderness, in contrast with those areas where man and his own works dominate the landscape, is hereby recognized as an area where the earth and community of life are untrammeled by man, where man himself is a visitor who does not remain.”

In a Senate hearing in 1963, Zahniser referred to this sentence, noting:

“In this definition the first sentence is definitive of the meaning of the concept of wilderness, its essence, its essential nature — a definition that makes plain the character of lands with which the bill deals, the ideal.”

The first sentence in Sec. 2(c) of the Wilderness Act that Zahniser was referring to contains two key defining qualities of Wilderness. First, Wilderness is to be in contrast to areas where human civilization dominates the landscape. Secondly, Wilderness is to be untrammeled, a place where the earth and its community of life remain uncontrolled and free of intentional manipulation by humans. Wilderness is to remain self-willed land, where the earth and its community of life are shaped by natural processes, not by human will. The first sentence in Sec. 2(c) essentially defines wilderness as special places that are set apart, places where humans interact differently with nature than we do in any other landscape, places where humility, restraint, and respect must guide our interactions with these places rather than a primary emphasis on human use, convenience, and utility.

When questioned about choosing the word untrammeled instead of undisturbed Zahniser explained that he had very carefully selected the word untrammeled after “dissatisfaction with almost every other word that had been suggested.” He explained why the word undisturbed did not express his intent:
“The problem with the word “Disturbed” (that is, “Undisturbed”) is that most of these areas can be considered as disturbed by the human usages for which many of them are being preserved; that is, temporarily disturbed. The idea within the word “Untrammeled” of their not being subjected to human controls and manipulations that hamper the free play of natural forces is the distinctive one that seems to make this word the most suitable one for its purpose within the Wilderness Bill.”

The word untrammeled therefore is not based on the current physical appearance of the landscape. Untrammeled does not mean “untrampled” or “undeveloped.” It is the forces of nature that are to be left untrammeled. The definition of untrammeled lays out the kind of relationship that we as humans are to have with wilderness. It defines how we will interact with wilderness. We are to allow Wilderness to be self-willed, not controlled and manipulated by our own human goals and desires. Being in contrast to civilization and untrammeled by human control and manipulation are key to the very meaning of Wilderness, and are what differentiates Wilderness from other undeveloped landscapes.