You wouldn’t expect someone who’s retired to need a vacation, but when my writing instructor at the University of Washington announced that we’d have two weeks off for spring break, I decided I wanted a real vacation, one that involved leaving home.

My Alaska Airlines miles had been gathering dust for years. My expired companion fare coupons disappeared long ago in the kitchen junk drawer. Time to collect some of my “rewards.”

My first idea was to travel to Guanajuato, Mexico, where we used to visit every summer. I rejected this plan when the airfare totaled what we paid to go to Madrid last fall and the schedule required us to spend a couple of leisurely days or nights at an airport.

Honolulu became my next choice when I learned that we could use our air miles to fly first class, round trip for $10, forgetting that the costs of food and lodging for a week in Waikiki would match what we paid for 18 days in Spain.

I’ve chosen to focus on only one of the many expensive activities tourists can enjoy in Honolulu, the equivalent of sparing you a look at all our travel photos.

Honolulu tourist activities take place well above sea level — helicopter rides and parasailing; at sea level — whale watching, sailing and surfing; and underwater. For our big splurge, or should I say plunge, we chose to travel below the sea. Since neither of us is a diver or even a good swimmer, we opted for a submarine ride.

The Nautilus, the submarine in Jules Verne’s adventure, Twenty Thousand Leagues Under the Sea, operated at depths well below those reached by the Atlantis submarine we sailed on. The fictional boat could dive to four leagues, or about 10 miles. Ours scraped bottom at 120 feet.

Verne’s story featured a giant sea monster capable of damaging an ocean liner. Its most famous scene pitted sailors in battle against a giant squid. Our story featured many small and colorful fish and a few large ones, all of which were pretty. None posed a threat to our safety.

According to our underwater tour guide, natural reefs off the coast of Waikiki have been disappearing for a hundred years. Artificial reefs, “a series of concrete pyramids,” are helping recreate new habitat for coral, fish, spiny urchins and other marine life.

Two scuttled ships and an airplane also aid in the recovery process. Large openings in these structures give cover for predators waiting to attack smaller fish. The boat moved fast enough that we could avoid witnessing this ambush.

The Atlantis accommodated 64 passengers with one viewing porthole for every two people. The trip was peaceful, the fish calming. Our only battle took place in a restaurant that evening as we fought with forks over a plate of calamari.

It was bad enough that the week in Hawaii came to an end, worse when we arrived in Seattle to hail and a snowstorm and the cat we boarded in a cat hotel refused to come home.