A CUBIT is 18 inches long. Noah's Ark was said to be 300 Cubits long, 50 Cubits wide, and 30 Cubits tall, making it about 450 feet long, 75 feet wide, and 45 feet tall.
(Multiply Cubits by 1.5 to get feet.)

Feet, Miles, Chains, Furlongs, Paces, Rods, and Leagues are all related:

A CHAIN is 66 feet, as is 1/10 Furlong. There are 80 Chains to the mile.
A FURLONG is 660 feet. There are 8 Furlongs to a mile.
A ROD is 5 1/2 yards, and there are 40 Rods in a Furlong, and 320 Rods in a mile.
An ACRE is 43,560 square feet, or, if the acre is square, 208.71 feet on a side. There are 640 Acres in a square mile.
A MILE is 5,280 feet in length, and also 1000 PACES.
A LEAGUE is 3 miles.

An A.U. (Astronomical Unit) is 93,000,000 miles, the distance from the Earth to the Sun.
A LIGHT YEAR is 5.880 trillion miles, the distance that light travels in a year.
A PARSEC is 3.26 Light Years. If you want to know why this curious number is used, it is the distance from earth at which a stellar parallax is one second of arc.

A PECK is 8 quarts, or 8.810 Liters.
A BUSHEL is 4 Pecks, or 32 quarts.