parish routes. In the United States, county highways are denoted or signed in various ways, differing by state. In Wisconsin, county highways are marked with letters—with one- to three-letter combinations (i.e.: C, CC, or CCC). Wisconsin's county highways are frequently and clearly marked at most intersections. Because county road names are not exclusive, a state may have many county roads with similar or identical names. In states like Illinois, county highways are marked either with a number (usually one or two digits), a single letter followed by a one- or two-digit number (i.e.: V-34, A-29), or in Rock Island County, with letters like Wisconsin but on a blue pentagon marker. These highways are usually marked at the beginning of the highway and occasionally throughout the route; they cannot be relied on as geographic directions the way more major highways are (state or interstate). In New Jersey, there are two sets of county routes: the 500-series (500–599), part of a statewide system which usually run through multiple counties, but are county-maintained; and the non-500 routes which are usually contained within a single county and are repeated in different counties. The latter generally use numbers in the 600-series; some counties have routes in the 700s and 800s. Two counties, Bergen and Monmouth, along with some routes in Ocean County, have routes outside this range with one- or two-digit numbers along with some numbers in the 100s. New Jersey's county routes are usually signed just as well as state routes (with mile- and half-mileposts), and will appear on freeway exit signage. In Iowa, secondary roads are defined simply by the Iowa Code as "those roads under county jurisdiction." The 99 counties in Iowa divide the secondary road system into farm-to-market roads and area service roads. Farm-to-market roads are maintained by the county and, paid for from a special fund: the Farm-to-Market Road Fund consists of federal secondary-road aid and 8% of Iowa's road use taxes. The farm-to-market road system is limited to . Unlike most states, Iowa's signed secondary roads are not numbered on a county-by-county basis. With exception to County Road 105, secondary roads use a uniform numbering grid using one letter and two or three numbers, e.g., E41. County roads running primarily east and west are assigned letters (from north to south) A through J. County roads running primarily north and south are assigned letters (from west to east) K through