Many cities and countries worldwide from the earliest BC to 2017 are still impoverished with the gap between the rich and poor growing annually. 'Slum Tourism' -- despite its controversy -- is a way for travelers to know more about poverty in specific areas of the world such as Brazil, India, Africa, Peru and even America.

In Mumbai, India, Dharavi is well-known as 'slum tourism' destination with locals as tour guides. Dharavi -- while teeming with waste -- is actually a waiting area for recycling material, which are often waste or discarded containers of water, milk or other items. The tour is said to show the other side of poverty; that people in these destinations are bustling with activity and do not moan about their lives.

Cape Town, South Africa is known to allow township tours to tourists and has once raised controversy when some locals said their town has tourists that treat the town as a "safari" by taking photographs in tour buses. The township tours are still offered and all proceeds -- as with all slum tours -- go to local charities and even locals themselves.

Rio de Janeiro, Brazil's Rocinha "Favela" is known for its mountain slum homes by the thousands. Some visitors said tourism of the "Favelas" in Rio is "capitalizing and marketing" slums as a tourist destination where the rich "feel better about themselves" after their visit.

According to News.com.au, Peru international tourists would often take a break from Machu Picchu tours and contact agencies to access Lima's impoverished cities. The news website cited Haku Tours founder Edwin Rojas -- who arranges tours to these locations -- who said the tours "are honest with visitors who come to get to know my country."

According to Conde Nast Traveler, after Hurricane Katrina, many areas of New Orleans have become temporary shantytowns. Some artists and businesses had pledged to help raise funds for Hurricane Katrina victims -- thus forming slum tourism in the area. In different remote locations in cities and rural countrysides of America are exhibits and even shows in impoverished areas that showcase the gritty reality to win over funding for its recovery.