Wallenda family high-wire artists cross speedway without net. Watch.

Wallenda family sister-and-brother tightrope artists Nik and Lijana Wallenda crossed NASCAR’s Charlotte Motor Speedway on Saturday on a single high wire at the same time -- in opposite directions.

Halfway there, Nik Wallenda had to step over his sister.

It was one of several gasp-worthy moments by the two members of the Flying Wallendas, a family known for generations of daredevil performances. The pair performed without harnesses, cables or safety nets. The wire was 460 feet long and suspended 150 feet high, according to Associated Press.

Nik Wallenda told the news organization he and his sister had “never performed this high and this far apart before.”

In 2012, Nik crossed Niagara Falls -- on a cable 1,800 feet long and 180 in the air -- with a harness. Then in June, he completed a 1,400-foot-long walk across a 1,500-foot-deep gorge near the Grand Canyon without a harness.

Fearlessness runs in the Wallenda family, which has had its share of tragedy.

Patriarch Karl Wallenda, Nik and Lijana’s great grandfather, was founder and leader of the group. He fell to his death in 1978 at age 73 while crossing a wire between the towers of the Condado Plaza Hotel in San Juan, Puerto Rico. Nik Wallenda completed the walk in 2011 with his mother, Delilah.

During that walk, he kneeled and gave a kiss, a salute to his great-grandfather, “my biggest hero in life,” he told CNN.