Planned route Originally planned to run from
Port Huron, Michigan, to
Charlotte, North Carolina, I-77 appeared on the original
Interstate System route numbering plan in 1957. The part of
I-94 from
Detroit, Michigan, northeast to Port Huron was originally planned as I-77 in 1957; the current I-77 was I-79. When the current I-79 was added in
Pennsylvania, the I-77 designation was moved to its current route, but the I-77 in Michigan also remained in the 1958 numbering plan, so the designation followed
I-90 and
I-75 in order to keep it continuous; the designation north of I-77's westward turn was to have been
Interstate 177 (
I-177). I-77 in Michigan later became part of I-94. Initially,
US Route 21 (US 21) traveled from Marietta to Cleveland. In 1962, I-77 debuted in
Akron and
Canton. By the end of 1971, US 21 was decommissioned in Ohio in favor of I-77 which was nearly complete. It was eventually finished in 1976 with the final connection being opened in
Independence. ==Exit list==