Convert from block [Midwest U.S.] to legua [Spanish, post-1568]

Unit Definition (block [Midwest U.S.])
The Block is an informal unit of distance popular in the U.S. A block is the average distance between street intersections in the rectangular street grids common in most American cities. The length of a block in many midwestern USA cities is about 1/16 mile or 100 meters.

Unit Definition (legua [Spanish, post-1568])
Unit of area used in the southwest US, equal to 25 labors, or 4428 acres (Texas), or 4439 acres (California). Also, a unit of length-- approximately three miles.