Hundreds of the nation's homeless and displaced citizens have banded together in small groups across the U.S. to form makeshift communities known as tent cities.

These communities are often times found in the woods, off of highways and under bridges. Some of them operate under a designated "mayor." Others are a free-for-all, and anyone can join.

Each community varies in terms of maintenance as some of them keep the area clean and drug-free and others are overflowing with garbage, old food, drug paraphernalia and human waste, CNN Money reported. According to the National Law Center on Homelessness and Poverty, encampments continue to rise while there is already estimated to be more than 100 of these tent cities scattered throughout the U.S.

"There have been increasing reports of homeless encampments emerging in communities across the country, primarily in urban and suburban areas and spanning states as diverse as Hawaii, Alaska, California and Connecticut," the law center stated in its study.

Many homeless people prefer to live in the tent communities rather than stay in a shelter, even if one is available, because there's more freedom compared to shelters' strict rules, CNN reports. A lot of shelters, for example, don't allow couples to stay together, require guests to check in and out of the facility and prohibit drug and alcohol use. In addition, homeless people who have served jail time don't quality for the free subsidies at shelters.

Several of the tent city residents CNN spoke with said tent cities are safer because of the sense of community that comes with living there.

According to the NLCHP, city or county officials only recognized eight of the encampments as legal, while other officials have looked the other way for another 10 tent cities. Most of the communities have been shut down, and its occupants have been evicted.

The organization said public officials should focus on developing affordable housing for their city's homeless.

"Encampments and tent cities have emerged as a means of self-help for homeless individuals to survive and find shelter, safety and a sense of community," the report stated. "Ultimately, the solution to the proliferation of encampments across the United States is the provision of affordable housing."