When Gordon Hartman watched his then-12-year-old daughter, Morgan, have trouble making friends in a swimming pool during a family vacation, he was heartbroken. The incident led Hartman to search for a public space where Morgan, who is on the autism spectrum and experiences a cognitive delay, could play with others who knew how to interact with her. Hartman soon realized such a place didn’t exist.

So, he made it himself.

Hartman is the founder of Morgan’s Wonderland, an ultra-accessible theme park in San Antonio, Texas, where people with or without disabilities can play together. It’s a place of total inclusion — a park where there are no barriers from keeping anyone from playing with each other.

“It’s a park for 100 percent of the people, not one for 90 or 80 percent of them, it’s for everybody, no matter how acute their special need may be,” Hartman tells PEOPLE.

“That’s what my dream was.”

The 53-year-old father began his pursuit of helping those with disabilities when he founded The Gordon Hartman Family Foundation after selling off his homebuilding business in 2005. After the incident in the pool — which is still hard for him to speak about — Hartman realized that if other children had a better understanding of people with disabilities, Morgan may have an easier time making friends. Hartman wanted to build a theme park that incorporated people with and without special needs like no other place before it. “It’s about not letting anyone feel different,” Hartman explains. “That’s what we tried to do with this park.”

Hartman held dozens of meetings to raise money and collaborated with architects, engineers, doctors, and therapists to design the $35 million park. Construction began in 2007 and was completed three years later, and just this year, the nonprofit added a fully-accessible $17 million water park called Morgan’s Inspiration Island.

Among many attractions, Morgan’s Wonderland includes a fully-accessible train, playground, and Ferris wheel. The water park features a wheelchair-accessible river ride and areas with warm water to help those with muscular conditions. The park also provides special wrist bands that can track the whereabouts of visitors, which is handy for those with autism, who are often considered flight risks.

Morgan’s Wonderland has had more than a million visitors since it opened, and one-third of its staff includes people with special needs. Admission is free for anyone with a mental or physical disability. But the parks are funded through donations, and Hartman says they operate at a loss — losing about $1 million a year — and they largely depend on fundraising.

Today, Morgan is 23, and while she has the cognitive abilities of a 5-year-old, she is doing better than years before. Hartman says she is a rallying point for him and others, and she is a true inspiration to the entire organization — that is why they named the water park, “Morgan’s Inspiration Island.”