It's about one-and-seven-tenths times as long as The 405.
In other words, 198 kilometers is 1.699 times the length of The 405, and the length of The 405 is 0.58858 times that amount.(a.k.a. I-405, Interstate 405, San DIego Freeway) (Southern California)
It's about one-and-seven-tenths times as long as Hadrian's Wall.
In other words, the length of Hadrian's Wall is 0.59 times 198 kilometers.(a.k.a. Roman Wall, a.k.a. The Wall, a.k.a. Vallo di Adriano, a.k.a. Vallum Aelium, a.k.a. Severus' Wall) (from North Tyneside, Tyne and Wear, England, United Kingdom to Cumbria, North West England, United Kingdom)
It's about one-and-nine-tenths times as long as The English Channel.
In other words, 198 kilometers is 1.85 times the length of The English Channel, and the length of The English Channel is 0.541 times that amount.(average width between Isle of Ushant and The Walde Lighthouse) (La Manche, Ärmelkanal, Mor Breizh, Mor Bretannek) (a.k.a. The Channel)
It's about two-fifths as long as The Grand Canyon.
In other words, 198 kilometers is 0.444 times the length of The Grand Canyon, and the length of The Grand Canyon is 2.25 times that amount.(a.k.a. Gran Cañón) (Arizona) (Colorado River miles measure)
It's about two-and-a-half times as long as The Panama Canal.
In other words, the length of The Panama Canal is 0.43 times 198 kilometers.(Canal de Panamá) (Panama)
It's about one-tenth as long as The Rhine.
In other words, 198 kilometers is 0.15 times the length of The Rhine, and the length of The Rhine is 6.67 times that amount.(a.k.a. Rhein, a.k.a. Rijn, a.k.a. Rhin, a.k.a. Rain, a.k.a. Reno, a.k.a. Rhenus, a.k.a. Ryn) (from near Reichenau, Switzerland through Hoek van Holland, Rotterdam, Netherlands)
The Rhine river runs 1,320 km in total length. The World War II Battle of Arnhem, as memorialized in the 1974 book and 1977 movie A Bridge Too Far, was the first of several attempts to capture key bridges across the Rhine, beginning with the Arnhem Bridge in the Netherlands.
It's about seven-and-a-half times as tall as Olympus Mons.
In other words, the height of Olympus Mons is 0.14 times 198 kilometers.(a.k.a. Mount Olympus) (Mars)