Delhi to Meghalaya is a flight, not a drive. Non-stop flights to Guwahati run 2.5 hours, and from there it is a scenic 3.5-hour road climb to Shillong. Most Delhi travellers do a 6 to 8 day Meghalaya trip. It is a long enough haul that day-trippers do not bother, which is part of the reason the state has remained less crowded than Himachal or Uttarakhand.