Town Walls
Work on the town's defenses first began in 1265, but the outline of the wall you see today dates to the 14th century. By its heyday in the 16th century, the wall was 1.5 miles long, 45-50 ft. high, up to 9 ft. thick, and included 46 towers! These days about 1 mile of the wall is still standing.
-Tallinn, Estonia