For the purposes of this chapter, the Township of Willistown is hereby divided into 20 classes of districts, which shall be designated as follows:

The boundaries of said districts shall be shown upon one or more map or maps attached to and made a part of this chapter, which shall (collectively, if there is more than one) be designated the "Zoning Map of Willistown Township." Said map or maps and all the notations, references and other data shown thereon are hereby incorporated by reference into this chapter and shall be as much a part of this chapter as if all were fully described herein.[1]

The boundaries between districts are, unless otherwise indicated, either the center lines of streets or railroad rights-of-ways, or such lines extended, or lines parallel thereto. Where figures are shown on the Zoning Map between a street and a district boundary line, they indicate that the district boundary line runs parallel to the street line at a distance therefrom equivalent to the number of feet so indicated.

Where a district boundary line divides a lot held in single and separate ownership at the effective date of this chapter, the regulations as to the use in the less-restricted district shall extend over the portion of the lot in the more-restricted district a distance of not more than 50 feet beyond the district boundary line. For the purposes of this chapter, the districts shall be considered to be restrictive in the following order, listed from least restrictive to most restrictive: R-3, R-2, R-1, RA-1, RA, RU, O-P, HB, O, I, M, FPC, SSC.