The journey from Karanjia to Patna covers 600 km. You should travel to Tatanagar for a direct train to Patna (PNBE). Alternatively, road travel via bus is possible but long. The total travel time ranges from 12 to 15 hours.
Total Distance: 600 km by road, 500 km air distance.
Trains are frequent on this route.
Road travel is long and tiring.
October to March for pleasant weather in Patna.