Arriving at destination eight hours before hotel check in...Iceland, baby!

I can't speak specifically to Reykjavik, but logically, a hotel or B&B or any other accommodation can only allow you to check in that early if the room was previously vacant. If not, the previous occupant would need to vacate the room early enough to allow housekeeping to prepare it for the next guest, and I can't imagine housekeeping would be able to do that in time for a 7am check-in under most circumstances.

It wouldn't hurt to ask the hotel, of course. Let them know your arrival time and if they aren't at full occupancy, they may be able to help you.

However, I would caution you against the strategy of starting with a nap on your first morning. The best way to get over jetlag is to push through. Try to get as much sleep as you can on the plane, and then do your best to stay awake until a reasonable bed time. It won't be easy, but the alternative is that you will be spending your nights wide awake and your days dozing off.

Most hotels will have no problem allowing you to leave your luggage until your room is ready.

Good luck!

If a room is available, most hotels will let you check in early.

The problem with reserving a room but not showing up until 7 AM is the the reservation will be marked a "no show," you will be charged and they may not honor that reservation. If you want to try this, you'd have to contact your hotel and ask if they will do it.

I stayed at the Canopy by Hilton which is just over a year old. Great location, excellent service, the best included breakfast I've ever had. And everyone speaks fluent English. Not cheap.

The hotel should have a luggage room where you can store your gear until check-in time.

After that, the best thing to do is take the local time as given and do whatever you would do at that time of day.

I just wanted to second everything Lane and Frank II said.

1) If a room is ready, most hotels will let you check in early for no extra fee (some do have a fee for this).

2) If no room is ready, most hotels will let you leave your bags for free (again, so do charge a small fee for this). Be prepared to remove items you need for the day quickly, so you can surrender the rest of your luggage.

3) If you want to be guaranteed a room you can occupy on arrival, you will have to contact the hotel directly and clarify that this is what you want. Otherwise, they might mark you as a no-show when you don't check in at 6 PM the night before. You will usually have to pay for a full extra night, even though you're only using the room from 7 AM. Or you can investigate if there are hotels at the airport that rent for a few hours (some airports have this; I don't know if Keflavik does).

4) I'm not sure the best plan is to take a nap on arrival. You may never get over the jet lag that way. Everyone is different on this, of course.

Three very useful responses within a brief time. Thanks to all of the responders for excellent advice.
Overcoming jet lag will involve some wisdom because we are only going east by four time zones but going north so the daylight will only be about four hours per day. With two advisors recommending the get up and go approach, I think we should pay attention.
Am guessing we will try to sleep on the plane and then drop luggage off at the hotel and see places in and near Reykjavic.
Will take melatonin at dusk. I like the idea of the Hilton since am collecting Hilton Honors points.

I think we want to see a aurora borealis (clear skis needed of course), representation of geothermal points of interest, see a glacier and see something of a volcano. We have four full days. The 30 year old son wants to see CCP games' home office in Reykjavic. For the sights outside of Reykjavic, am trying to decide if we rent a vehicle or pay for the touristy excursions. I've read about the need to take all of the insurance with rentals. General advice appreciated.

It's okay to take a nap as long as you set your alarm. Take a nap then get up and get going.
There have been plenty of posts here about jet lag, and everyone has a different approach. In my opinion, there's no one or best way to do it. True, Iceland is tricky because it's not that far yet you'll still feel the effects of jet lag and the darkness at that time of year.

Have a good time!

Thank you, Rachel. Another authentic and caring post.

I am arriving the week before you.
Not to put a damper on your plans, but you might want to book a hotel asap.
I booked mine back in July, and there wasn't much in my budget then; and yesterday when I checked availability in Reykjavik to see if there was something better , there wasn't much to choose from at all!
Hotels seem to be full year round in Reykjavik from the research I have done.
People go in winter to see the Northern Lights.
As far as I know Iceland does not celebrate American Thanksgiving.

Have you taken Melatonin before? I ask, because it gave me some of the worst nightmares I have ever had. Others have told me the same.
One of them, I woke up screaming, scaring my husband.

Do go out and walk around rather than nap.

I've stayed at Base hotel. I thought it was functional and not expensive. The rooms are decent, new and clean - if a bit Spartan. I'd stay there again. It is closer to the Airport than Reykjavic.

I've had no issues with melatonin. It seems to make me sleepy, for initially getting to sleep, but wears off quickly so won't guarantee a full night's sleep. I used it last a couple nights ago after returning from France. I woke up in the middle of the night and took one to help me get back to sleep. Three hours later there was a little grogginess but it went away quickly - nothing like the Excedrin PMs I used to take on international flights. I've never taken more than one pill at a time (I think they are 5 mg each).