It's about 0.00000003 times as tall as a Mauna Loa.
In other words, 209 microns is 0.00000002280 times the height of a Mauna Loa, and the height of a Mauna Loa is 43,860,000 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 9,200,000,000 microns 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 0.00000002 times as tall as The Challenger Deep (Marianas Trench).
In other words, 209 microns is 0.0000000191710 times the height of The Challenger Deep (Marianas Trench), and the height of The Challenger Deep (Marianas Trench) is 52,162,000 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 10,902,000,000 microns 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 0.00000002 times as tall as Maxwell Montes.
In other words, 209 microns is 0.0000000190 times the height of Maxwell Montes, and the height of Maxwell Montes is 53,000,000 times that amount.(Ishtar Terra, Venus)
Maxwell Montes rises to a total height of 11,000,000,000 microns. 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 0.000000008 times as tall as Olympus Mons.
In other words, 209 microns is 0.00000000770 times the height of Olympus Mons, and the height of Olympus Mons is 130,000,000 times that amount.(a.k.a. Mount Olympus) (Mars)
The tallest mountain in the solar system, Olympus Mons rises to approximately 27,000,000,000 microns. 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 0.000000003 times as long as The Panama Canal.
In other words, 209 microns is 0.00000000240 times the length of The Panama Canal, and the length of The Panama Canal is 420,000,000 times that amount.(Canal de Panamá) (Panama)
Connecting the Atlantic and Pacific Oceans across the Isthmus of Panama, the Canal measures 88,000,000,000 microns in length. Ships passing through the Canal are raised (and then lowered) 26,000,000 microns above sea level through the lock-and-dam system.
It's about 0.000000002 times as long as The English Channel.
In other words, 209 microns is 0.000000001950 times the length of The English Channel, and the length of The English Channel is 513,000,000 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 107,000,000,000 microns, 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 0.000000002 times as long as The 405.
In other words, 209 microns is 0.00000000179340 times the length of The 405, and the length of The 405 is 557,600,000 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 116,540,000,000 microns. The 405 is the most heavily-trafficed freeway in the United States, with an average speed as low as 8 kph during rush hours.