Hi Maria,
It depends very much on the shape of the one acre lot. An acre is 43560 square feet and can be of any shape. Hence 14 acres is 14 43560 = 609840 square feet.
 If it is square then each side is of length √609840 = 780.9 feet so once around the four sides would be
4 780.9 = 3123.7 feet. There are 5280 feet in a mile and 5280/3123.7 = 1.7 so one and three quarter times around is more than a mile.
 If the lot is a circle then once around is 2768.3 feet. 5280/2768.3 = 1.9 so you need to go almost twice around to walk a mile.
 If the lot is a rectangle which is 500 feet wide then it is 609840/500 = 1219.7 feet long and once around is
1219.7 + 500 + 1219.7 + 500 = 3439.4 feet. 5280/3439.4 = 1.5 so one and a half times around is enough.
I hope this helps,
Penny
