We lifted our paddles from the water and let ourselves drift downstream. Deep in a wood, far from anywhere that was anywhere, unseen birds above burst into song in the canopy of spring-leafed trees. Up ahead, sunlight illuminated our way through a tunnel of greens and browns, melting as it touched the water. Emerald lettuce-like plants, blurred out of focus by the current, waved us on our way from below. The air flashed with bursts of blue as little squadrons of damselflies danced around us, heedless of the more cautious flight paths of dragonflies mating on the wing.

It’s fair to say that my companion and I were enchanted. It was as if the entrance to this long, narrow and thrillingly shallow rivulet – for which we’d had to scour a seemingly unbroken bed of reeds at the end of a lake – was a portal into a lost world.

Until this year I’d never heard of the Great Masurian Lakes, and didn’t know that Poland was home to many. However, to the east of Gdánsk, the province of Warmia-Masuria is known unofficially as the Land of a Thousand Lakes. “But that number’s not really right,” local guide Mariana told me. “There are more like 3,000 here.”

I’d reached the region’s capital, Olsztyn, with an Interrail ticket that had whisked me overnight from London via Berlin, giving me a sneak preview of the landscape through the train window. Unlike England’s Lake District, the scenery here is very flat – not quite the ironing-board flatness of the Fens but certainly a landscape that does not like to hem in its inhabitants. Deciduous woods are dotted with villages, hamlets and farmsteads; storks nest on the top of poles and grand, high-gabled manor houses. Pretty much everything else is water.

I spent a sultry day getting to know one of the north-eastern lakes – Mamry – by doing the gentle, 30-mile cycle tour around it, starting at the town of Węgorzewo. It’s one of 30 routes described in an excellent English-language guide (with maps) available free at tourist information centres. But before picking up my rental bike (£5 a day, wegorzewianka.pl) I popped into the neighbouring Ethnographic Park and Folk Culture Museum.

At the park, under the guidance of an expert weaver, I tried my hand at making a traditional rag rug on a handloom. My technique was a trifle ham-fisted, but watching the rug grow was rather satisfying.

Across the road at the museum, a wonderful confection in polished wood and glass was my favourite exhibit. “That,” declared the guide proudly, “is Węgorzewo’s first ever television. A local family won it in a competition in the late 1960s and had to go to Warsaw to pick it up. It would have been worth two to three months’ wages then.”

Setting off on our bikes, we found ourselves briefly on the Green Velo, the 1,240-mile waymarked trail that follows Masuria’s border with the Russian exclave of Kaliningrad before plunging southwards.

Our own route, along cycle paths and minor roads, brought us to Mamerki forest and the former headquarters of the Supreme Command of the German army. This was a grim reminder of the region’s violent past, and I was glad to leave the murky bunkers and return to the sunshine to climb the museum’s newly built 38-metre viewing tower.

The views over the lake proved a welcome antidote, as did a blissful freewheel soon afterwards down a lane flanked by hundreds of tall oak trees.

Teutonic knights ruled the area for much of the Middle Ages, so it was fitting to spend a couple of nights in one of their former castles, the Hotel Zamek Ryn (doubles from £75 B&B, including spa), which overlooks Lake Ryn. Before dinner I descended to the stronghold’s 14th-century undercroft for a relaxing dip in a little swimming pool. Appetite duly whetted, in a nearby lakeside restaurant I sliced into some placki ziemniaczane – crispy potato pancake, served with steaming vegetables chopped into a tomato sauce.

The next day we found ourselves in the Lost World, or the River Sobiepanka as it’s known to mapmakers. We’d hired kayaks at Sorkwity (£10 a day, mazurypttk.pl) and headed out over the sylvan-shrouded Lake Lampackie to paddle a section of the remarkable Krutynia river kayak route, a 68-mile paddlers-only trail that threads its way across the region along innumerable lakes and rivers.

When we arrived at the riverside garden of Bar Sobiepanka – several hours, lakes, grebes and red-crested pochards later – a family was singing old Polish folk songs a cappella around a table, while thousands of aspen seeds in feathery clumps drifted through the air, creating the impression of summer snow. Zbyszek, who had come to pick us up, along with his kayaks, cheerily explained why we’d had to resort to our map to find some of the tiny outflows from the lakes. “We put up a lot of signs on wooden poles to show people the way … but beavers came along and chomped them all down.”

And so back to Olsztyn, where 11 lakes lie within the city limits. On one of them, Ukiel, sits the ultra-modern Tiffi Boutique Hotel (doubles from £60 B&B). I lounged on its balcony, gazing at trick-pulling jet-skiers. Dinner at the lakeside Przystań restaurant next door was washed down with a bottle of crisp Warminskie Rewolucje beer from the local Kormoran brewery.

Olsztyn’s surviving medieval buildings include an impressive city gate that became a prison and then a fire station, and the Gothic castle where Renaissance-era mathematician and astronomer Nicolaus Copernicus made the calculations that contributed to the switch from the Julian to the Gregorian calendar in 1582.

On a walking tour with Anna, a guide from the town’s tourist office, we encountered a pleasingly foppish bronze statue of the great man beside the river Łyna. “You see how shiny his nose is?” Anna asked. “That’s from all the local people stroking it to bring them luck.”

I couldn’t help thinking – given the good fortune the inhabitants have in living here in the first place – that this was being somewhat greedy.

• The trip was organised by Polish Tourism Organisation. Travel was provided by Interrail (a pass for five days’ travel within one month costs £193 for youths, aged 12-27; £251 adults, 28+, and £226 for seniors, 60+). More info from mazury.travel and visit.olsztyn.eu

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