This story appears in the September 2018 issue of National Geographic magazine.
T MINUS ONE WEEK
Setting the sight line: After years of climbing up a pair of parallel limestone pillars in the mountains of Switzerland, photographer Thomas Ulrich and alpinist Stephan Siegrist wanted to walk between them. Three factors affect a highline walk: focus, balance, and altitude. Since the line crossed at the towers’ peaks, Siegrist would have no point of reference to focus on to keep his balance. “If you look straight, you see nothing—just air,” Siegrist says. To fix this, they placed a brightly colored backpack on top of the tower.
T MINUS ONE DAY
Essential Preparation: A cable car took Siegrist and Ulrich halfway up the Schilthorn mountain to the towers. They climbed both spires and bolted in anchors to run a line between them. The anchors must be extremely secure to create the high tension that makes the line walkable. They also needed:
- One harness for climbing up and another for walking across
- Chalk to keep hands dry
- Sunglasses and sunscreen
- No shoes—bare feet are best for feeling the line
T MINUS ZERO HOURS
Ready for launch: Rain would make the synthetic-fiber line slippery, but on this September morning there was only a light fog. Ulrich climbed a nearby ridge to get the shot, and Siegrist took a few practice steps to warm up and get a feel for the line’s tension. The first step is the riskiest: Falling too early puts you dangerously close to the rock face. “After three steps you need to relax or your nerves [transfer to] the rope,” Siegrist says. “If it works once, then it’s quite easy.”
BY THE NUMBERS
Elevation of Schilthorn in feet
Width of rope in inches
Feet from peak to peak