 Just north of Center City, I-77 makes a unique interchange configuration with Interstate 85, with north and southbound lanes crisscrossing briefly.Between I-85 (exit 13) and I-485 (exit 19), I-77 features the state's only HOV lanes.After I-485, I-77 reduces to five lanes (three lanes northbound), then to four lanes after Gilead Road (exit 23).