How long is 13 feet?
It's about 650,000 times as long as a Cell's Nucleus
The length of a Cell's Nucleus is about 0.0000200 feet.
(for animal cell)
It's about one-seven-hundred-thousandth as long as The Danube
The length of The Danube is about 9,350,000 feet.
(a.k.a. Donau, a.k.a. Dunaj, a.k.a. Dunav, a.k.a. Duna, a.k.a. Дунав (Dunav), a.k.a. Dunărea, a.k.a. Дунáй (Dunay), a.k.a. Tuna) (from Breg Martinskapelle, Black Forest, Germany through the Danube Delta, Romania)
It's about one-nine-hundred-thousandth as long as The Oregon Trail

The length of The Oregon Trail is about 11,500,000 feet.
(from Independence, Missouri to Oregon City, Oregon)
It's about one-nine-hundred-thousandth as long as The Volga
The length of The Volga is about 11,600,000 feet.
(a.k.a. Волга, a.k.a. İdel (Идел), a.k.a. Атăл (Atăl), a.k.a. Edil, a.k.a. İdil, a.k.a. Рав (Rav)) (from the Valdai Hills, Tver Oblast, Russia through the Caspian Sea)
It's about one-nine-hundred-fifty-thousandth as long as The Mississippi River

The length of The Mississippi River is about 12,360,000 feet.
(from Lake Itasca, Minnesota through Pilottown, Plaquemines Parish, Louisiana)
It's about 0.0000009 times as long as The Distance from L.A. to New York

The length of The Distance from L.A. to New York is about 14,700,000 feet.
(Los Angeles, California to New York City, New York) (via I-10 E, I-15 N, I-70 E, I-76 E, I-80 E, I-280 E)
It's about 0.0000009 times as long as I-80

The length of I-80 is about 15,216,600 feet.
(a.k.a. Interstate 80, a.k.a. Keystone Shortway) (net length)
It's about 0.0000007 times as long as The Great Wall of China (wall only)

The length of The Great Wall of China (wall only) is about 20,530,000 feet.
(长城, 長城, Chángchéng, a.k.a. 万里长城, 萬里長城, Wànlǐ Chángchéng) (a.k.a. "The long wall of 10,000 Li") (from Shanhaiguan through Lop Nur, China) (wall segments only)
It's about 0.0000006 times as long as The Amazon River
The length of The Amazon River is about 21,120,000 feet.
(from Nevado Mismi, Arequipa, Peru through near Marajó, Brazil) (approximate distance)
It's about 2,000,000 times as long as a Bacterium
The length of a Bacterium is about 0.00000660 feet.
(Escherichia coli) (rod-shaped configuration)
It's about 2,000,000 times as long as a Mitochondrion
The length of a Mitochondrion is about 0.000006170 feet.
(Eukaryotic; average)
It's about 0.0000005 times as long as The Great Wall of China (total)

The length of The Great Wall of China (total) is about 29,000,000 feet.
(长城, 長城, Chángchéng, a.k.a. 万里长城, 萬里長城, Wànlǐ Chángchéng) (a.k.a. "The long wall of 10,000 Li") (from Shanhaiguan through Lop Nur, China) (total length, all branches)
It's about 0.0000003 times as long as The Diameter of Earth
The length of The Diameter of Earth is about 41,851,290 feet.
(Equatorial)
It's about 0.00000010 times as long as The Circumfrence of Earth
The length of The Circumfrence of Earth is about 131,479,700 feet.
(Equatorial)
It's about 0.00000001 times as long as The Distance from Earth to the Moon
The length of The Distance from Earth to the Moon is about 1,261,275,000 feet.
(a.k.a. Luna) (median of semi-major axis, or apigee, and semi-minor axes, or perigee)