Word of warning: If heights make you twitchy, you probably should move on to the next post.

Four men were arrested Monday and accused of skydiving (or base jumping, if you prefer) off of 1 World Trade Center in September, an act condemned by the New York police commissioner and the Port Authority of New York and New Jersey.

The act didn’t go unnoticed last fall. Police in New York said at the time that they were investigating the incident after surveillance cameras caught two men landing near the Goldman Sachs building in lower Manhattan.

The video, posted to YouTube on Monday and flagged by the New York Daily News, appears to be taken from the helmet camera of one of the three men who jumped (the fourth stayed on the ground). Watch it if you want to experience what it’s like to stand atop 1 World Trade Center before leaping off and parachuting down onto the streets of lower Manhattan, if that sounds like your cup of tea, if watching that kind of video won’t immediately leave you stricken with vertigo. (The actual jumping begins at about 2:30 on the video.)

This is the second time this month that someone has been charged after sneaking into the site. One of the men arrested Monday said he and the others got in through a gap in the fence, according to the Associated Press. That’s also how a 16-year-old from Weehawken, N.J., got in there this month, authorities said. The teenager climbed through a hole in the fence and made his way to the top of 1 World Trade Center, authorities said, where he hung out and shared photos on Twitter.