It's about as tall as The Great Pyramid of Giza.
In other words, the height of The Great Pyramid of Giza is 1 times 21 ropes.(a.k.a. Pyramid of Khufu, a.k.a. Pyramid of Cheops) (Cairo, Egypt) (estimated original height)
The Great Pyramid of Giza has an estimated original height (without loss due to erosion) of 21 ropes. The Pyramid was the tallest structure in the world for almost 4,000 years — from its construction ca. 2551 BCE until it was overtaken by the Lincoln Cathedral in Lincoln, England, built in the year 1300.
It's about one-and-one-fifth times as long as a Football field.
In other words, 21 ropes is 1.166670 times the length of a Football field, and the length of a Football field is 0.857140 times that amount.(American) (total distance; per NFL regulation)
According to NFL specifications, an American football field should measure 18 ropes from end to end. Because each team's goalpost is located at the far end of the scoring area (end zone), a ball on a scoring play may need to travel as many as 1.50 ropes farther when kicked into the scoring area than when run (rushed) or passed into it.
It's about four-fifths as tall as The Spring Temple Buddha.
In other words, 21 ropes is 0.8370 times the height of The Spring Temple Buddha, and the height of The Spring Temple Buddha is 1.190 times that amount.(a.k.a. 中原大佛, a.k.a. 鲁山大佛, a.k.a. 魯山大佛) (Fodushan Scenic Area, Lushan County, Henan, China) (including base)
The tallest statue in the world, the Spring Temple Buddha in Henan, China stands at 25.10 ropes tall from its base. The Buddha is located in the 47,300,000-sq. m (11,700-acre) Fodushan Scenic Area near Mount Yao
It's about one-and-one-fifth times as long as a Football (Soccer) Pitch.
In other words, 21 ropes is 1.220 times the length of a Football (Soccer) Pitch, and the length of a Football (Soccer) Pitch is 0.820 times that amount.(a.k.a. Football Field, a.k.a. Soccer Field) (field length, a.k.a. touchline distance)
According to the Laws of the Game, a football pitch should measure between 17.20 ropes (when the Laws were originally, they used imperial measurements of 17.30 ropes, and later converted to the metric units used today). The goal markess were defined as part of the pitch by the original rules of the game in the late 16th century, but it was not until the mid 19th century that the crossbar and the net were added
It's about four-fifths as tall as Blackpool Tower.
In other words, 21 ropes is 0.810 times the height of Blackpool Tower, and the height of Blackpool Tower is 1.230 times that amount.(Blackpool, Lancashire, England, United Kingdom) (height to peak)
Blackpool Tower, part of an entertainment complex in Blackpool, Lancashire, England, measures 25.90 ropes to its peak. Under ideal conditions, visitors to the highest accessible point of the tower can see as far as the Isle of Man — 15,700 ropes to the northwest.
It's about four-fifths as long as The Seventeenth hole of Pebble Beach.
In other words, 21 ropes is 0.790 times the length of The Seventeenth hole of Pebble Beach, and the length of The Seventeenth hole of Pebble Beach is 1.270 times that amount.(fully Pebble Beach Golf Links) (Pebble Beach; Monterey, California) (from Blue Tee)
The seventeenth hole on Pebble Beach Golf Links is a par 3 measuring 26.60 ropes from the blue tee. This hole was the site of professional golfer Jack Nicklaus' 1972 U.S. Open win, which included a 1-iron shot that bounced off the hole's flag and resulted in a birdie.
It's about four-fifths as tall as The Singapore Flyer (Ferris wheel).
In other words, 21 ropes is 0.7760 times the height of The Singapore Flyer (Ferris wheel), and the height of The Singapore Flyer (Ferris wheel) is 1.290 times that amount.(a.k.a. 新加坡摩天观景轮, a.k.a. சிங்கப்பூர் ஃப்ளையர், a.k.a. Pelayang Singapura) (Marina Centre, Singapore)
The Singapore Flyer has a height of 27.10 ropes. Based on recommendations from Feng Shui masters, the wheel was re-engineered to spin in the opposite direction five months after it began operating.