List of cities from CLAY's county

DOCTORS INLET	FLEMING ISLAND
FLEMING ISLE	GREEN COVE SPRINGS
GREEN CV SPGS	KEYSTONE HEIGHTS
KEYSTONE HGTS	LAKE GENEVA
MIDDLEBURG	ORANGE PARK
ORANGE PK	PENNEY FARMS

What is ZIP Code?

ZIP codes are a system of postal codes used by the United States Postal Service (USPS) since 1963. The term ZIP, an acronym for Zone Improvement Plan,[1] is properly written in capital letters and was chosen to suggest that the mail travels more efficiently, and therefore more quickly, when senders use the code in the postal address. The basic format consists of five decimal numerical digits. An extended ZIP+4 code, introduced in the 1980s, includes the five digits of the ZIP code, a hyphen, and four more digits that determine a more precise location than the ZIP code alone. The term ZIP code was originally registered as a servicemark (a type of trademark) by the U.S. Postal Service, but its registration has since expired