Interstate 680
Interstate 680 may refer to:

Interstate 680 (California), a connecting freeway between I-80 and I-280 in the San Francisco Bay Area, California
Interstate 680 (Nebraska–Iowa), a bypass in Omaha, Nebraska
Interstate 680 (Ohio), a loop through Youngstown, Ohio
Interstate 676 in Pennsylvania and New Jersey, designated as Interstate 680 back when I-76 was I-80S

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