We paddled our kayaks with reverence into a narrow-mouthed harbor on Deer Island's east coast. Rocky forested headlands sloped to a shoreline edged with clumps of thick seaweed. An eagle rose from a lookout's nest that a hunter would envy. I built up momentum with power strokes to glide silently through an abandoned fishing weir whose posts rose at angles from the sea: weathered wood totems in honor of departed fishermen.

Rounding a bend of Northwest Harbor, we saw a more modern weir, very much in the seine-netting business, followed by a long rocky beach, and an old fishing shack. Having paddled into Canada from Eastport, Maine, we pitched tents in the sloping grassy yard of Malena and Bruce Smith, who ran a local outdoor adventure company called Seascape Kayak Tours.

Anyone can paddle from the United States to Canada here. There's a customs post on Deer Island, across from Eastport, Maine, and, with a phone call and proper identification, the border procedures are standard. But the passage is not for beginners. Although I'm no more than an intermediate ocean kayaker, I was paddling with five experts who were on a much longer journey all the way from Cape Cod to Nova Scotia. The Smiths were the local experts on my short segment, responsible for guiding the six of us into Northwest Harbor.

I had joined GOMEX, The Gulf of Maine Expedition, in Eastport and been briefed on their trip the previous day at "the Boat School," Down East Maine terminology for the Marine Technology Center campus of Washington County Technology College. There I met Natalie Springuel, leader of the trip and president of the Maine Association of Sea Kayaker Guides and my other teammates. I would be following these master kayakers the next day like a collie puppy in a strange neighborhood full of muscular pit bulls.

How strange was the neighborhood? The seawater, for one thing would take your breath away. It's mostly 50 degrees F in summer, from around 37 in February, a mere 12 degree fluctuation throughout the year. Drysuits, dry tops, and life vests would be worn at all times while over this sea.

Then there was "Old Sow," the largest tidal whirlpool in the Western hemisphere. Every six hours on each incoming and outgoing tide, the area between Dog Island and Deer Island, not far from where we would land for customs, comes alive with eddies, riptides, whirlpools, and, once in a bad moon, water gyrating 12 to 20 feet in the air. The really large whirlpool, at 250 feet across, happens only when tides are highest and strong winds blow.

The tides were another factor. We would be dealing with 25-foot tides at every campsite, although further along the New Brunswick coast, in the Bay of Fundy, tides are the highest in the world at 50 feet. The kayaks had to be secured at the high water mark or we would wake without them.

Reaching Eastport, the GOMEX paddlers had already completed over three-quarters of their 1,000-mile kayak journey. Community events at stops along the way had been organized to educate people about the Gulf of Maine: its oceanography, watersheds, natural history, people, and its burgeoning business of aquaculture. When I met them, the group had spent five nights in beds out of the 82 nights paddling to New Brunswick. My three nights with them were a blip along the way.

We paddled in an arc around Moose Island, which is what Eastport sits on, with Canada's Campobello Island guarding the eastern horizon. The Americans, British and Canadians had been squabbling over boundaries here since they began being drawn. Eastport, in fact was the last occupied town in US history with the British capturing it during the War of 1812. It was then given back to the Americans in an agreement that eventually included renunciation of US claims to Grand Manam, Deer Island, and Campobello.

We crossed an invisible line at sea that had us in Canada before noon. After letting a small car ferry go ahead, we slipped onto the shore at Doctors Cove near Deer Island Point and walked to the customs house. We met Bruce Smith there where he guided us through the calm seas around Indian Island to the smaller islands of Popes and Casco. Minke and humpback whales, porpoises and harbor seals all treat this area as their playground.

The birdlife around the smaller islands was astonishing with herons and eagles, terns and Bonaparte's gulls all going about their fishy business. Bruce had timed the tides and we'd been lucky with weather, a perfect paddling afternoon as he guided us into his home port of Northwest Harbor.

Our next day's plan was to paddle north around the tip of Deer Island through a narrow channel named Doyles Passage and on to a campsite on uninhabited Pendleton Island. The paddling challenge began for me as we entered Doyles Passage. As rocky cliffs sloped down on both sides of us, I could sense a change in current speed. We were clearly on a river in the sea and had to watch as it pushed us close to rocks and eddies and slipped us down over rapids. It was exciting but not hard as the quickening current was with us. I moved to the front as the least experienced kayaker so that if I went over, experts behind me would quickly spot trouble.

As soon as I exited Doyles Passage, all hell broke loose. The wind around the head of Pendleton Island caught my kayak just as the current changed. I nearly tipped and my spray skirt, which kept seawater from getting inside the kayak, slipped open. I had instantly become a potential deadweight in rough water as the tips of waves wet my lap.

Natalie quickly paddled next to me and stabilized my boat with her arms as I stretched the rubber of the skirt around the opening. I hadn't even had to say anything but that was the beauty of paddling with the president of Maine Sea Kayaking Guides. I regained composure and pushed off once again. The wind had built up the waves, rising two or three feet with wave sets very fast. I admit that I just wanted to step onto the sturdy land that lay ahead.

Pendleton was ours for the night. While one of our team cooked a meal of oriental noodles covered with freshly-picked beach peas, I pitched my tent back from the high dune in a pine glade abutting the dense interior spruce forest. Amid cries of "Put on your bug lotion if you go in there," I wasted no time in getting settled. The forest floor was a natural sleeping mat of dry moss and fir needles, my feet springing up with every footfall. I rested in the quiet of my glade and listened to strange birdsongs. Only at 9:30 pm did the sun set and the singing stop. I recognized a loon's cry and an owl's hoot then an unfamiliar fetching melody as the sky grew dark.

The last leg of my kayaking journey was potentially the most worrisome - a sweep straight across Passamaquoddy Bay to St. Andrews on the New Brunswick mainland, five nautical miles of open sea. Reassuringly, the bay was like a peaceful pond as we set off. Entering open waters there was a steady wind but it was at our backs, pushing us where we wanted to go. We talked about world travel, school days, future plans. Soon Navy Island, just off St. Andrews, grew along the horizon and then we were up on its beach.

My friends had another month of kayaking left, but I was ready for a real bed and a hot shower.

Maine Office of Tourism offers information and a free travel planner, www.visitmaine.com or Eastport Maine Chamber of Commerce, www.eastport.net.

Tourism New Brunswick has a free travel guide, www.tourismnewbrunswick.ca.

New Brunswick kayak rental and tours: Seascape Kayak Tours, www.seascapekayaktours.com.

Travel Health Insurance.

Peter Aiken has written for the New York Times, Toronto Globe & Mail, Los Angeles Times, Boston Globe, Islands Magazine, Discovery, Travel Holiday and many more. Travel stories have appeared in Travelers' Tales India and Travel Unlimited. He has contributed to two guidebooks on New England, and edited the Access Guide to Cape Cod, Martha's Vineyard, and Nantucket. Email: paiken@hotmail.com.