Take an overnight 3A train from Ahmedabad to Delhi or Chandigarh for comfortable and efficient travel; Delhi route is recommended for better connectivity and frequency.
Take a Volvo or Himachal Road Transport Corporation (HRTC) bus from Delhi or Chandigarh to Kasol; buses operate early morning and take around 12-14 hours; Chandigarh to Kasol is shorter (~8-9 hours) and more scenic.