Perhaps no other city in America is more famous for being home to the mega-rich than Dallas, Texas. It is not just the oil industry that has helped many in the area amass their fortunes. The lack of state income tax in Texas helps make it an attractive place to call home for many billionaires.

1. Alice Walton

Perhaps no one has benefited more from the Wal-Mart effect than Alice Walton, daughter of Sam Walton, who founded Wal-Mart in 1962. With an estimated net worth of $46 billion, Alice Walton is the richest person in Texas. Unlike her brothers Rob and Jim, Alice is not involved in the company and focuses on her extensive art collection, which is worth more than $500 million. She opened the Crystal Bridges Art Museum in her hometown of Bentonville, Arkansas, in 2013. The museum features a Frank Lloyd Wright-designed home that she had moved from New Jersey, as well as works by Andy Warhol, Norman Rockwell and Georgia O'Keeffe.

Walton put her two massive Dallas-area ranches on the market in 2015 for a combined asking price of $48.5 million. Featuring over 5,872 acres of rolling hills, river frontage and horse ranching facilities, the land also has extensive oil and gas reserves. While she is leaving the ranching business to focus on her art museum, she plans to remain in the area, living in a home she owns in Fort Worth.

2. Andrew Beal

A self-taught math genius, Andy Beal has amassed a $9.4 billion fortune by expertly identifying and buying distressed assets. During the California blackouts in 2001, he acquired bonds of power companies and debt backed by airlines following the 9/11 terrorist attacks. Proven to be one of the smartest investors in the country, Beal can forecast market trends and identify how to profit from them. A college dropout, he became a billionaire following the financial crisis after buying weakened assets all over the country.

Beal owns various banks and firms in Dallas and Las Vegas, and he regularly gambles against the world's greatest poker players in high-stakes games worth millions of dollars. In 1993, he developed a sophisticated mathematical equation called the Beal Conjecture that has stumped mathematicians worldwide despite a $1 million reward.

3. Robert Rowling

Robert Rowling has become one of the wealthiest investors in America after selling his oil and gas assets for $477 million in 1989. Rowling has turned Omni Hotels into one of the world’s largest and most lucrative luxury hotel and resort chains, representing the majority of his estimated $5.5 billion net worth. His company, TRT Holdings also owns the Gold's Gym fitness chain, and in 2014, it purchased five additional luxurious golf resorts and spas across the U.S. worth a reported $900 million.

5. Ray Lee Hunt

Ray Lee Hunt is the son of famed oilman H.L. Hunt, who is said to be the inspiration for the character J.R. Ewing of the TV show "Dallas." The apple did not fall far from the tree, as Ray Lee Hunt has grown his father's fortune to an estimated net worth of more than $5.3 billion. While Hunt has profited from the shale boom, Hunt Oil focuses on international holdings, investing in huge oil finds in Yemen and Peru. His company also has major real estate holdings including Hyatt Hotels and some of the most highly profitable commercial properties in Dallas.

4. Kelcy Warren

The Barnett Shale, a rock formation that underlies a 25-county area of North Texas, has made countless Texans rich – but with a net worth of $4.8 billion, Kelcy Warren tops them all. The famed formation has produced trillions of cubic feet of natural gas, and Warren’s Dallas-based company, Energy Transfer Partners, transports it through a vast system of pipelines including the Dakota Access Pipeline. Warren's company acquired rival Williams Co. for $37.7 billion, combining to create an enormous infrastructure controlling more than 100,000 miles of oil and natural gas pipeline across the United States.