Around 500 km distance will be there if a superfast train from Katihar to Patliputra starts via purnea - saharsa - khagaria - barauni - hajipur - sonpur at night. It will be a very good option for these areas. From katihar the train should start at 9 pm and reach patliputra at 6 am. Then this train will become popular and give good revenue as well.