Bardia National Park is situated in Western Terai Region of Nepal in Bardia District and there are various ways to reach Bardia National Park.
From Kathmandu:
Daily buses run from Kathmandu to Mahendranagar or Dhangadi via Ambassa Bardia. The drive takes about 13 hours long journey with beautiful views, as you pass through hills and forests and then through the mainly flat and rural Terai.
There are also daily flights from Kathmandu to Nepalgunj Airport which takes around an hour and it makes your journey shorter and easier.
From Pokhara:
Daily buses run from Pokhara to Mahendranagar or Dhangadi via Ambassa Bardia. The journey takes around 12 hours with beautiful green hills, forests, river and then through mainly flat and rural Terai.
From Lumbini:
Catch a bus from Lumbini to Butwal which will takes around 2-3 hours drive. Get off at Butwal and you will find many buses to Mahendranagar or Dhangadi which takes around 8 hours drive and get off at Ambassa Bardia.
From Butwal:
There are many buses runs from Butwal to Mahendranagar or Dhangadi via Ambassa Bardia and the journey will take around 8 hours.
From Nepalgunj:
Bardia National Park is about 87 km far away from Nepalgunj and one can catch a bus that goes Mahendranagar or Dhangadai via Ambassa then change the bus to Thakurdwara for Bardia National Park. The drive takes around 3 hours by public bus.
If you are coming from India via Nepalgunj, Nepalgunj is about 16 km from Indian Border called Rupaidiha.