Things to do in Near Black Diamond Beach

If you are doing the zodiac boat tour of the Jukulsarlon lagoon, you may not have extra time. When we did it two years ago, we had to suit up with thermal suits in case anyone fell in, but we had to wait for the boat before us to return, before there were enough suits. By the time we finished and unsuited, it was a lot close to 2 1/2 hours than 1 hour. If your tour is in fact 1 hour, you can walk along the glaciers and take pictures, and there are food trucks in the parking lot if it's mealtime. We didn't make it to the Black Diamond beach across the road, but that could be pretty interesting to check out after the boat tour. You may not to have to kill as much time as you think (unless your friends' tour goes longer, also.)

I was thinking of doing the regular boat tour. Another question. We are going to drive there and back to Reykjavik on the same day. Is it worth the 10 hours in the car?

The weather will be a big factor in planning your day. I visited the Glacier Lagoon in late September. It was so windy that we could barely stand or walk! (One of the smaller people in our group was literally blown over.) Boat tours only ran for part of the day. We did quite a bit of (slow!) walking along the shore, and found a somewhat sheltered place where we could sit and take photos.

The Black Diamond Beach is beautiful!

Be sure to check weather conditions and forecasts closely before leaving Reykjavik. It is a long drive to Jokulsarlon; in late October you will do much of your driving in the dark. You may want to consider spending one night somewhere west of the Glacier Lagoon so you can relax and don't have to make the long drive back to Reykjavik in the dark on an unfamiliar road.

ehike, I agree that you should not try to do this in one day from Reykjavik. There is so much to see in the area that you'll want more than just one very long day.