Transportation in New York City City and Fort Lee, New Jersey, is the world's busiest bridge in terms of vehicular traffic. New York has historically been a pioneer in tunnel construction. Most carry rail lines, but there are four exceptions. The Lincoln Tunnel, which carries 120,000 vehicles per day under the Hudson River between New Jersey and Manhattan, is the world's busiest vehicular tunnel. The Holland Tunnel, also under the Hudson River, was the first mechanically ventilated vehicular tunnel in the world and is considered a National Civil Engineering Landmark by the American Society of Civil Engineers. Two other notable tunnels connect Manhattan to other
New Jersey English New Jersey, plus Middlesex and Monmouth Counties. Therefore, the short-"a" system of these areas of New Jersey is most similar to the New York City split-"a" system, however with some variation. East of the Hackensack River, Labov finds the short-"a" system to occurs with no more variation than in New York City proper. However, west of the Hackensack River, he finds that the normal function word constraint of New York City English is lost and the open syllable constraint becomes variable. While most of the New York metropolitan dialect heard in New Jersey is rhotic, that of Newark and Jersey