The long answer is, well, read the link that BoxingJohn posted, and also read the Top Questions in the Grand Canyon forum. A trip to Havasupai requires some planning, including getting a permit and an overnight reservation.
Or, you could just read the replies in your other thread:
It is an 10 mile hike. It took my boys 3 hrs to the village (8 miles). Hard to say from the village to the falls as we stopped and played at the New Falls, and they went my speed.
Make that a EARLY start from Vegas...You will be hiking during the hottest part of the day Carry a gallon of water and leave nothing in the car at the isolated trail head, parking area ...carracar
May's a popular month for the Havasu hike, so make sure you have reservations. There are no other options other than the lodge or campground in Supai.
Depending on the weather, you might want to make it later in the afternoon than earlier. Statistics say average max temps at Supai are in the 90's in May. I see you're from Sweden -- I'm not sure if you have any dessert hiking experience but dessert heat is something to be taken seriously. Treat it like high atltitude hiking; it's not about being physically fit. If it's a warm day, take a headlamp and calculate back from sunset and allocate 3.5 hours for the hike. Manage your water carefully.
Most people hiking down to Supai stay somewhere in the area for one night, and arrive at the hilltop parking before sunrise so that they are hiking down at the coolest part of the day.
I am going at the end of May, and the lodge is fully booked. Reservations begin 12 months ahead of time.
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