Convert from twain to kilometer

Unit Definition (twain)
The twain is an old word for the number two, derived from the Anglo-Saxon twegen. The American author Samuel Clemens (1835-1910), who had been a riverboat pilot on the Mississippi in his youth, took his literary name from a traditional riverboat phrase "mark twain", meaning "exactly two" fathoms of water. This was the minimum depth needed for the boats to operate safely without running aground.

Unit Definition (kilometer)
The kilometer is one of the most common metric units of length or distance. One kilometer equals exactly 1000 meters (metres), about 0.62137119 mile, 1093.6133 yards, or 3280.8399 feet.