We took my husband's 75-year-old grandmother to Iceland. We still talk about that trip 9 years later.

The author with her husband's grandmother, Nanny, in Iceland. They're standing on the continental divide in Þingvellir National Park. Courtesy of Laura Leavitt When my husband's grandmother turned 75, his family planned a trip to Iceland for her. Seven of us went for four days, and it was a fantastic time. We traveled well together and made lasting memories. I still remember when I first got the email from one of my husband's cousins about his grandmother's upcoming birthday: "Nanny loves to…