New Yorkers strolling in Central Park might have seen an odd sight today: men with dirt on their faces strapped in harnesses rappelling down a large rock near the Center Drive/East Drive entrance.

They were participating in a condensed version of the Bear Grylls Survival Academy, a five-day course where average people can learn Grylls’ extreme survival techniques. The academy launched in November 2012 and the five-day courses will begin in Scotland this July. This event was hosted by VisitScotland as part of Scotland Week, a celebration of all things Scottish in the U.S. and Canada.

This crash course was led by Scott Heffield, the academy’s lead instructor. Heffield is a professional mountaineer who worked with Bear Grylls on his TV show “Man vs. Wild.”

The event provided a sneak peek at some of the skills taught at the academy, including navigation, basic combat maneuvers, and fire-making techniques. But no Bear Grylls survival-related event would be complete without drinking or eating something that might make a normal person vomit.

Heffield dumped a handful of dirt into a canteen and shook it up to make his own blend of Central Park water. He took a drink and passed it around to illustrate that there might be survival situations where people can’t spend the time to apply skills that take more time to accomplish.

“Bear’s way is you got to move fast to get to rescue so you might have to drink rancid water,” he said.

That’s all well and good, as long as people can get to safety before the dysentery hits. Of course, Heffield highlighted the dangers of drinking foul water, and ways to minimize the risk of illness or death.

“So it’s this situational awareness and making decisions on the spot–dynamic risk assessment. Can you do it, can’t you do it,” he said.

The Central Park cocktail was followed by a special treat to end the event: a live mealworm, which everyone ate.