My college roommate came to town, her first visit to San Diego since we graduated an undisclosed number of years back. “I have limited time,” said Crystal, “and I want to see it all, by land, by air, by water, whatever. You set it up, Eve, and I’ll take you along as my guest.”

My pleasure. A good excuse to be a tourist in my own town for a couple of days.

From the airport, I whisked my old roomie over to Davanti Enoteca in Little Italy, where we had a couple of ginger pear bourbon mules ($12) and shared a mascarpone polenta with pork shoulder ragu ($18) and talked tours.

“If we want to go big, we can do an air tour,” I began. “San Diego Helicopter Tours offers tours over the city. The 45-minute one caught my eye. Taking off from Gillespie Field, you fly over Miramar, Rancho Sante Fe, Del Mar racetrack, then south over the beaches, over the San Diego Bay, downtown, Balboa Park, and the zoo. For 45 minutes of flight time, it will cost $450 [sdhelicoptertours.com; 888-399-5460].

“Or we could try a slower, lower, open-air biplane tour,” I continued. “Wind in our faces, we sit in the front, pilot in the back, flying over San Diego in a 1920s biplane. You could channel your inner Amelia Earhart and rock an old-school helmet.” The Barnstormer Hop, a 20-minute tour with Barnstorming Adventures, costs $219 (barnstorming.com; 800-759-5667).

I chuckled at the thought of the always perfectly coiffed Crystal in a leather flying helmet. She must have been thinking the same thing because she said, “I could have sworn I saw hot air balloons flying off to the north as the plane descended into San Diego this afternoon.”

“Yes, you probably saw the balloons that tour over Del Mar.” Sky’s the Limit Ballooning Adventures offers a Del Mar Coastal Champagne Evening Adventure. A 45-minute to hourlong flight time, taking in the sights at sunset, for $215 (sandiegoballoonrides.com; 760-602-0295).

“What are our water options?” asked Crystal.

“We could take a two-hour harbor cruise, take in the sights of San Diego Bay,” I continued. “The Hornblower cruise leaves from the San Diego Navy Float and takes in views of the Cabrillo Monument, Coronado Island, Shelter Island — 13 miles of sailing the bay [hornblower.com; 619-686-8715]. Tickets run $29 for adults. And if you want to see a little San Diego while getting a workout, we could head over to Mission Bay for some paddleboarding,” I suggested. “SUP Diego offers two-hour tours on the bay for $55 per person [supdiego.com; 619-206-0664]. Or we could go with a kayak outing, explore on our own,” I added. “Mission Bay, two and a half hours, a single kayak is $25; a tandem, if you want to share, for $30 at Aqua Adventures [[email protected]; 619-523-9577].”

“Let’s get our own kayaks,” laughed Crystal. “Remember the last time we tried to work together on something?” The memory of that failed lab project made us laugh like a couple of freshmen again.

“On land,” I said, still chuckling, “we could see the Gaslamp, Balboa Park, Midway with a Segway tour. I have always wanted to try them out. Another Side of San Diego Tours offers a two-and-a-half-hour tour of the Gaslamp, the bay, and Balboa Park for $149. The tour hits the rose garden in Balboa Park as well [anothersideofsandiegotours.com; 619-239-2111].

“If we’d rather not Segway our way around town, we could try the yellow GoCars,” I added. “They are a GPS-guided mini car and they leave out of Little Italy. They offer a three-hour tour starting at $132 for two people, and it goes to Shelter Bay, Point Loma, and Ocean Beach. Sounds like fun [gocartours.com; 800-914-6227].”

“Eve, you’re just envisioning the Instagram possibilities, aren’t you?” laughed Crystal. “Me in a helmet and a mini bright-yellow car zooming around San Diego. I know you.”

“Well,” I deflected, “you can’t leave San Diego without touring San Diego’s craft-beer scene. I think we should catch Brewery Tours of San Diego’s $95 Friday-evening tour at 6:00 p.m. It’s a tasting at Ballast Point, dinner and tasting at San Marcos Brewery, and another tasting at Stone Brewery. Tour is done by 11:30 p.m. [brewerytoursofsandiego.com; 619-961-7999].”