ROCKFORD, Ill. (WTVO) — Zip Rockford, a zipline adventure course at Alpine Hills Park, says it will not open this summer due to a labor shortage.

Alpine Hills is located at 4402 Larson Avenue.

“Due to a lack of response to our employment searches, we are not able to locate zip guides for operations.  As circumstances change, we may be able to alter this decision, but as of now, we are not able to open this summer,” the park said on its website on Friday.

Job openings, and people quitting their jobs, have reached record highs.

The Labor Department said that employers posted 11.5 million job openings in March, and 4.5 million Americans quit their jobs. The gap between open jobs and available workers hit 5.6 million, another new high.

Experts said workers feel confident they can find better pay or working conditions elsewhere. A shortage of labor supply has caused a surge in wages, but that surge has not kept up with inflation.