How thin was Charles blondin tightrope?

Charles Blondin's tightrope was approximately 1.5 inches (about 3.8 cm) in diameter. This thin rope was used for his famous tightrope walks across Niagara falls in the mid-19th century, where he demonstrated remarkable skill and balance. Blondin's performances drew large crowds and showcased his daring feats as a tightrope walker.