Early morning sunlight filtered through mist as I began kayaking the other day from a quiet cove into the open waters of Maine’s Moosehead Lake.

The wispy haze soon dissipated, revealing an enormous mountain on the distant horizon – Katahdin, at 5,269 feet, the highest summit in Maine. Penobscot Native Americans called this peak “Kette-Adene,” which meant the “greatest mountain.”

In his book “The Maine Woods,” Henry David Thoreau, who canoed on Moosehead during expeditions in 1853 and 1857, described the 75,000-acre lake as “a gleaming silver platter at the end of the table.” Dotted with more than 80 islands, it is the largest mountain lake in eastern United States.

Although I have climbed Katahdin several times, I had never kayaked on Moosehead, and, after launching from a public park in the village of Greenville at the lake’s southwestern end, savored a view of unbroken forest and rugged hills.

Unlike Thoreau, who chronicled the Moosehead voyages and a Katahdin climb in his book, “The Maine Woods,” I did not traverse the lake’s 40-mile length, but turned around after a few miles and returned to the park. I had a different mission: Persuade an old pal, Rocky Tremblay, to join me on a short kayak excursion.

Rocky had been born in Greenville and spent his early childhood there while his father worked as a firewatcher on lookout towers; the family moved to West Haven, where I grew up, after his dad left the forest service.

Rocky spent his summers as a lifeguard; my afterschool shift at McDonald’s didn’t start until late afternoon, so I spent mornings rowing a tiny pram up and down the beach. I usually stopped by Rocky’s stand to chat or play cards if nobody was swimming.

Rocky – now a retired physics professor and chair of the math and science department at Gateway Community College in New Haven – bought a family cabin in Greenville a few years ago and has been restoring it. He had invited me and two other longtime friends, Steve Caldwell and Dave Mahon, for a visit.

“Do you realize we haven’t been in a boat together since that fateful night?” I asked Rocky.

I was referring to a madcap voyage he and I embarked upon decades earlier. It had been my very first outdoor adventure, and almost my last: a 15-mile, nighttime row across Long Island Sound in my 8-foot vessel.

I had been planning this Labor Day excursion all summer with another friend, but he bailed out the night before. I wasn’t about to go alone, so rowed over to Rocky’s lifeguard stand.

“Hey, do you want to row across the sound with me?”

Rocky didn’t hesitate.

“Sure. When?”

“Tomorrow night.”

“OK.” Though he had never rowed in my craft, the USS Mini-Boat, Rocky had competed on the swim team and figured he could survive if our tiny boat flipped over.

The next night, our girlfriends loaded The Mini-Boat onto the roof of their car and drove us to Bridgeport, where we carried the rowboat aboard a ferry to Port Jefferson, Long Island. Once ashore, we lowered the boat off a pier, climbed aboard, and began rowing side-by-side, each to an oar. It was exactly midnight.

We carried a gallon of water, a couple PB&J sandwiches, a flashlight, compass, nautical chart and lifejackets.

“It was stormy,” Rocky recalled, describing large swells that kept our boat bobbing once we exited 2-mile-long Port Jefferson Harbor and entered the sound.

About 2 a.m., a school of bluefish bumped repeatedly against our hull. Then, Rocky noticed a large shape appear above the surface on his side of the boat. Initially, I was blissfully oblivious.

“I thought it was a buoy,” Rocky said. “Then I realized it was moving with us.”

He kept quiet, not wishing to alarm me, but eventually I noticed this enormous fin.

“It’s a blankety-blank shark!” I shouted.

The giant predator, which was longer than our boat, surfaced every few minutes, its dorsal fin rising higher than our gunnel.

For the next dreadful hour or so we rowed silently, waiting for the shark to flick its tail and knock us overboard, or take a bite out of the wooden hull. Then, just as silently as it appeared, the menacing fish swam away.

Moments later, another crisis: A mysterious light appeared to the east. There was no sound of a boat engine, so when the light kept getting closer, I feared we were in a rip current and would be sucked out to sea.

I flicked on my flashlight and pulled out the chart. It depicted an area marked “DANGER. LIVE MUNITIONS,” indicating a restricted military zone.

We seemed to be drifting toward this area, but then I exclaimed, “Wait a minute! We’re not in a current! The light is moving!”

It was a conning tower of a submarine, mostly submerged and heading toward us.

Rocky and I frantically steered our boat out of the sub’s path, while it slipped silently past, no more than 50 yards away. I doubt if our rowboat showed up on radar.

Exhausted after rowing all night, we could barely see the Connecticut shoreline through morning fog, but as it burned off, Charles Island materialized, just off Milford. Rocky and I had hoped to land several miles farther east, but decided we would head for the closest shore in Stratford.

I heard what sounded like carpenters hammering shingles on a roof, but quickly determined these were rifle shots from a firing range. Happily, the shooting stopped by the time we landed, staggered to a bar at the shooting club, and asked to use the phone.

Half an hour later, our girlfriends arrived, and brought us home.

You’d think that after that experience, Rocky and I would become lifelong landlubbers. He later bought a fishing boat and has ventured far offshore; I switched to kayaking and have since paddled across Long Island Sound several times (always in daylight).

Well, I’m happy to report that Rocky agreed to climb aboard my tandem sea kayak in Maine the other day, and we took a turn around West Cove on Moosehead Lake.

“Not bad,” he said, as we zipped along.

“And no sharks,” I said. “Not even a minnow.”