This was an amazing experience, and I highly recommend it! But I wanted to write about our experience for the benefit of others. Let me start off by saying we *might* have “fudged the numbers” a bit on the whole “be moderately fit” prerequisite. I had had an ACL/MCL reconstruction one year to the date prior to our hike, and my wife had had a cervical spinal surgery about six months prior. We are also both plus-sized. However, we read in many reviews that the hike in was easy and only about a mile. We knew we could handle that. So we decided to go for it, because this was a bucket list dream of mine. While the hike was relatively flat, there are spots where there are big rocks to climb over that are more than your average step. We learned on the hike that these caves change every year, and because the ice recedes every year, what may have been true a few years ago may not be accurate today in terms of the duration and difficulty of the hike in to the glacier. We were consistently bringing up the rear, but hanging in with our group of mostly 20-something hiker types. But even one of them said, “the reviews said it was a mile, but that was way more than a mile, and it said easy, but it was ALL rocky.” Yep, that about sums it up. We checked our steps on our phone after and it was closer to five miles round trip, and almost all of it was VERY rocky. Flat, but more difficult than a walk due to the rocky terrain. Having said that, it was SO WORTH IT! Something else to note—this year, there were steps carved into the ice to get into the cave, and they were steep and made of pure ice. There is a rope anchored to the side wall to hang on to while entering the cave. We were both able to manage it, but something worth noting. Our guide, Alex, was awesome, and helped us on the few spots where we had to scramble over bigger rocks. He was also patient with us and made sure we were behind him, because on the trip back, I’d say we reached the car about five minutes after the young bucks on our tour. We tipped him generously, (which is not a common practice in Iceland, but he very much deserved it) and he literally hugged my wife in thanks! He never made us feel bad or uncomfortable for being slower than the rest of the crew. With that said, you do need to be able to hike a moderately quick clip through unstable rocky terrain. We had some collapsible walking sticks in our bag that we broke out on the hike back that really helped.