TULSA, Okla. (AP) — The first phase of what will be one of the biggest parks in the U.S. is set to open this weekend in Tulsa.

A Saturday parade and concerts will mark the opening of the $465 million Gathering Place. The 100-acre stretch along the Arkansas River will include bike and walking trails and sports courts. Admission is free, but equipment rental will cost.

The public park has been built with private money, led by billionaire philanthropist George Kaiser. Funders and city leaders say the park will be a space for recreation and culture but also an ambitious model for inclusivity.

For...