Wow. I forgot to multiply by 24. That was embarrassing. That significantly increases the area a party would need to search. To over 200000 square miles. However, natural terrain would probably significantly lessen that, and the fact that realistically if you're planning on beating the Tarrasque, you'll probably have flight capability, and how hard would it be to look for a hole in the ground big enough to fit something as big as the Tarrasque?