We reached Rock Harbor in the late afternoon, and to our relief, we had our pick of campsites. There were even shelters available. We looked at one, but decided that we simply preferred to sleep in our tents.

We took off our packs, but before we set up camp, we walked down to the visitor center and store. We were able to dispose of the trash we had packed out of the backcountry, and I wanted to see if I could get a pair of flip-flops and a cuticle scissors (I’d packed mine, but taken them out to use them before we left, and never put them back in my pack). The store had neither, but Sean found National Parks Scrabble, Ritz crackers, and potato chips, and Adam bought an ice cream on a stick and a Coke.

We checked the events schedule and saw that there was an 8pm presentation on Isle Royale Geology 101 at the auditorium, so we decided to go. The board also had this photo, encouraging visitors not to feed the wildlife, but if you must feed something, feed a ranger:

We went back to our site and set up camp amid the only pesky mosquitoes of the entire trip. It was the first time any of us had needed our mosquito netting, which seemed remarkable.

We tucked into our final dinner in the backcountry: smoked salmon with dill couscous and peas. Sean had suggested bringing the as yet unopened package of salmon my parents had given us for Easter, and it was the perfect treat!

After supper we explored Rock Harbor some more on the way to the auditorium for the 8pm presentation.

The presentation was given by Justin Olsen, a grad student working on his masters degree in geology at Michigan Tech. He was spending the summer at Isle Royale researching, presenting, and working as a volunteer ranger. Justin was engaging, informative, and good humored. He chatted with his audience before the talk, including with two precocious kids, twins John and Eva.

The iPad couple were also in the audience. As were other people we recognized from the ferry and the visitor center.

Justin talked about the formation of Isle Royale from lava flows laid down on a supercontinent that existed and broke up before Pangaea. The Greenstone Flow, the largest on the planet, was 1,200 feet thick and took 1,000 years to cool. Millions of years of additional lava flows and the weight of sedimentary rock that built up on it caused it to buckle and create the massive basin that an Ice Age glacier would scrape out before melting to form Lake Superior. The cliffs of the Keweenaw Peninsula and the Greenstone Ridge on Isle Royale are the the edges of the same Greenstone Flow.

Among many other topics, Justin touched upon why the ecology of the other, southwest end of Isle Royale is so different from the end we were on. The final massive glacier, as it retreated, stopped 11,000 years ago halfway along Isle Royale. Essentially, the glacier sat there for hundreds of years, depositing silt on the southwest side before suddenly retreating rapidly. Hence, the southwest side has much deeper, richer topsoil than the thinly soiled northeast.

After Justin’s talk, we were exhausted and headed back to camp and to bed.

Next morning dawned overcast, while we were stirring, several loons flew overhead. Phil and Adam went to see about check-in time at the lodge, while Sean and I had some oatmeal and began breaking camp.

We had some time to kill before check-in, so we browsed the books in the visitor center, among our purchases were Rolf Peterson’s The Wolves of Isle Royale: A Broken Balance and Candy Peterson’s memoir, A View From The Wolf’s Eye.

We strolled around Rock Harbor and had lunch at the Greenstone Grill, which had not received its expected stock of various supplies earlier in the week.

After lunch, our room was ready at the lodge.

We didn’t have a whole lot of time to freshen up because we needed to be back at the visitor center for the 1pm Harbor Walk and Interpretive Talk with Ranger Casey. The topic was Isle Royale’s isolation.

One of the most interesting things about the talk was where it took place, on the America Dock off the edge of the natural peninsula that created the Rock Harbor marina. Ranger Casey explained that the dock had been the main arriving and departing dock for the America, a luxury steamer out of Duluth, and one of the most important supply ships to Isle Royale resorts in the early years of the twentieth century.

The ship sank in 1928, although all the passengers except a dog survived. One of the America‘s life boats sits on the dock.

After the talk, we headed back to our room, not to clean up and relax, but to get ready for our final hike, an afternoon loop to Scoville Point.