It's about one-one-hundred-fifty-thousandth as tall as a Mauna Loa
In other words, 6.70000 centimeters is 0.0000073080 times the height of a Mauna Loa, and the height of a Mauna Loa is 136,800 times that amount.(Hawaii) (Hawaiian island volcano) (total height from seafloor)
Mauna Loa, one of the five volcanoes which forms the island of Hawaii and the tallest mountain in total height in the world, rises to 920,000 centimeters above the seafloor. The peak of Loa is home to the approximately 6,000 sq. m (0.6 ha) Lake Waiau, one of the highest altitude lakes in the United States outside of Colorado.
It's about one-one-hundred-fifty-thousandth as tall as The Challenger Deep (Marianas Trench)
In other words, 6.70000 centimeters is 0.00000614570 times the height of The Challenger Deep (Marianas Trench), and the height of The Challenger Deep (Marianas Trench) is 162,720 times that amount.(near Marianas Islands, a.k.a. Ladrones Islands, northwestern Pacific Ocean) (depth below sea level)
The Challenger Deep, at the southern end of the Marianas Trench, reaches a depth of 1,090,200 centimeters below sea level. There has been only one manned expedition to the bottom of Challenger Deep — a 1960 voyage that took 4 hours and 48 minutes to reach the bottom.
It's about one-one-hundred-fifty-thousandth as tall as Maxwell Montes
In other words, the height of Maxwell Montes is 160,000 times 6.70000 centimeters.(Ishtar Terra, Venus)
Maxwell Montes rises to a total height of 1,100,000 centimeters. Since Venus does not seem to have the kind of tectonic activity which gives rise to mountains on Earth, the origin of the Venusian mountain remains the subject of some dispute.
It's about one-four-hundred-thousandth as tall as Olympus Mons
In other words, 6.70000 centimeters is 0.00000250 times the height of Olympus Mons, and the height of Olympus Mons is 400,000 times that amount.(a.k.a. Mount Olympus) (Mars)
The tallest mountain in the solar system, Olympus Mons rises to approximately 2,700,000 centimeters. The mountain has been known to astronomers since the nineteenth century because it is tall enough to rise above Mars' frequent dust storms.
It's about 0.0000008 times as long as The Panama Canal
In other words, 6.70000 centimeters is 0.000000760 times the length of The Panama Canal, and the length of The Panama Canal is 1,300,000 times that amount.(Canal de Panamá) (Panama)
Connecting the Atlantic and Pacific Oceans across the Isthmus of Panama, the Canal measures 8,800,000 centimeters in length. Ships passing through the Canal are raised (and then lowered) 2,600 centimeters above sea level through the lock-and-dam system.
It's about 0.0000007 times as long as The English Channel
In other words, 6.70000 centimeters is 0.0000006260 times the length of The English Channel, and the length of The English Channel is 1,600,000 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)
The English Channel measures between 10,700,000 centimeters, narrowing as it flows northeast. The world speed record for a Channel crossing by swimmer was set by Australian Trent Grimsey in 2012, with a time of 6 hours, 55 minutes.
It's about 0.0000006 times as long as The 405
In other words, 6.70000 centimeters is 0.000000574910 times the length of The 405, and the length of The 405 is 1,739,400 times that amount.(a.k.a. I-405, Interstate 405, San DIego Freeway) (Southern California)
Running from Irvine to San Fernando, The 405 runs a total of 11,654,000 centimeters. The 405 is the most heavily-trafficed freeway in the United States, with an average speed as low as 8 kph during rush hours.