Some 1,000 people, many of them with their families and children, marched with their breasts covered or uncovered down the pedestrian mall that runs through downtown Denver.
"This is a way to show that men and women can go topless in the streets and still set respectful and healthy boundaries," one participant in the Denver march said, providing only her first name, Sandra.
"This is a way to promote gender equality and a reminder that nudity and sex are not the same," she said, adding that "to appreciate the female body does not mean to stop respecting women, because #NoMeansNo."
Some of the demonstrators carried posters with phrases like "Free the nipple", "Your body is not a mistake" or "Let's make the body normal again".
The marches, held annually on the Sunday before Women's Equality Day, which was established by the US Congress in 1971 in memory of August 26, 1920, when American women established the right to vote.
Topless is not prohibited in Denver and, although rarely practiced, is not considered "indecent exposure" by law.
In New York, women going topless was legalized in 1992, but in other cities such as Phoenix, Arizona, Corpus Christi, Texas or Madison, Wisconsin, it is not.
Because some of these local laws which prohibit going topless are not consistent with state legislation, there are a number of unresolved court cases regarding their constitutionality.
Only three states prohibit women to go topless: Indiana, Tennessee and Utah. And in another 14 states, including Arizona, Florida and Nevada, the laws are "ambiguous," meaning that while they don't prohibit going topless for women, they include it among the acts that are "disturbing the peace," which can lead to an arrest.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)