NIAGARA FALLS, N.Y. - All 4,000 free tickets to see Nik Wallenda's tightrope across Niagara Falls from the American shore have been snatched up.

Vouchers for the June 15 event were gone shortly after the New York parks department began offering them online Friday morning. After being redeemed for wristbands, they assure access to Terrapin Point, the only place from the U.S. side of the falls that'll give spectators a clear view of Wallenda as he starts across around 10 p.m.

The walk can also be seen on jumbo screens in the park and city of Niagara Falls.

No tickets are needed to watch Wallenda from the roomier Canadian shore.

Wallenda says he prefers to walk from the U.S. to Canada but may have to reverse course, depending on the weather.