A horse-keeping district should be generally 20 acres or more in size and must be at least 15 acres in size including the area of all dedicated streets contained therein, and all lots or parcels of property contained within its boundaries shall be contiguous. The boundaries of said district shall be drawn so as to coincide as nearly as practicable with street alignments or other clearly discernible topographic features. (Ord. 1364 § 1, 1971; Ord. 1212 § 1, 1969; prior code § 33.601(A)(5)(a)).