One of my favourite recent photographs is of me (unusually), perched on the bonnet of our car, about to set off on a solo, two-week road trip from our Sussex home to the wilds of Scotland, taking in Eryri (Snowdonia), Lancashire, the Lake District and Yorkshire. I had no idea that the research trip I was about to embark on – for my book, which traces the story of British holidays over 400 years – was going to reveal my homeland as somewhere I barely knew.

As a southerner, it was the northern half of Britain that I needed to discover. I’d stitched together my route with visits to museums, archives and classic seaside resorts that had once blazed so brightly. I’d visited Cumbria before, but the Conwy coast, the Lancashire countryside, Blackpool, Morecambe, Scarborough? All these were unknowns.

My first stop was Eryri, where it turned out my hotel, the Royal Oak in Betws-y-Coed, had been welcoming artists such as JMW Turner since the late 18th century. Fifty years later, it became the hub of the country’s first artists’ colony, drawn here by the dramatic beauty of the dense, bottle-green swathes of the Gwydir Forest and the spectacular peaks of the Glyderau range and Moel Siabod.

Over coffee, hotel manager Katie Valentine told me about the artists who called the area home – David Cox, Henry Clarence Whaite and Thomas Collier among others – at least until Betws railway station opened in 1868. “At that point,” she said, “many moved to houses further up the valley, grumbling that the place was becoming flooded with tourists.” As I would discover on this journey, it seems overtourism is far from a contemporary travel trend.

From Eryri, it was a short hop to Llandudno, a beach town so pristine it felt a little like a Victorian theme park resort. “In some ways it is,” Judith Phillips, trustee of the Llandudno Museum, told me. “The family who built Llandudno in the mid-19th century – the Mostyns – still own much of it now, and control everything from what colours people can paint their hotels to what businesses are allowed on the promenade.”

The Llandudno Museum made plain that much of our history is not in the great city museums, but in libraries, archives and small museums on quiet high streets, often run by passionate volunteers with an encyclopaedic knowledge of their local heritage.

Driving from Llandudno up to Lancashire along the North Wales Expressway, I whipped in and out of tunnels, emerging to see great swathes of the cobalt-blue Irish Sea stretching to the horizon.

Further into my journey, I was pointed towards early editions of the very first guidebooks to the Lake District, written by Thomas West and William Wordsworth, at the Armitt Library in Ambleside; shown handwritten letters by Queen Victoria at Blair Castle (including her personal recipe for potato salad); and told wonderful stories of Wakes Week holidays in Blackpool by the dapper Richard Croisdale at Blackburn Museum – their longest-serving volunteer, at a sprightly 90 years old.

Blackburn’s grandiose Victorian museum and Bolton’s neoclassical town hall stand as legacies of the era when Lancashire towns were affluent manufacturing bases home to tens of thousands of factory workers. The Georgian streets of Richmond are like a mini Bath, but steeped in Yorkshire heritage. But perhaps nowhere confounded my expectations more than Blackpool.

Arriving on a Friday night, the promenade buzzed with lights and life; the illuminations blazing all the way to the tower, kids skipping along the seafront entirely unaware they had been brought to one of the most deprived towns in the country. “We are a town of extremes,” said Claire Smith, co-owner of the chic Number One South Beach B&B. “We have pockets of absolute joy next to complete caverns of woe. There’s no blending. It’s either amazing or awful.”

Claire and husband Mark shared stories of Blackpool in the 1970s, not least his coming back from the pub as a teenager to find his parents had let his bedroom – along with their own – to guests, leaving them to sleep in the lounge. This was the era when guests queued in their dressing gowns to use the bathrooms, landladies locked the doors between mealtimes, and peach Melba was the height of culinary flair.

“They were simpler times, people expected much less,” Claire told me, a little wistfully. “But I do think people were happier.” There’s still plenty of joy to be found, though. When I visit the Pleasure Beach as it opens on a Sunday morning, families are streaming in; the first coasters rattling skywards; a general air of giddy excitement that is a stark counterpoint to the rundown streets elsewhere in the town.

So many of my preconceptions were corrected or reversed: the elegant St George’s Hotel in Llandudno showed me that not all grand dame seaside hotels are faded or old-fashioned. And while we do love to run down our own seaside resorts, I saw beaches to rival anything the Med has to offer, from Scarborough’s South Bay to Morecambe’s vast, empty sandscapes.

Beyond the seaside, it was Scotland that really blew my mind. Following in the footsteps of William and Dorothy Wordsworth, who toured the Highlands and Lowlands for six weeks in 1803, I headed up the western flank of Loch Lomond, entirely unprepared for what I was about to discover. Dusk was falling as I drove across Rannoch Moor – a silent, pockmarked moonscape that seemed entirely bereft of life, save for a lone pair of car headlights, somewhere up ahead. And then, in the distance, great, hulking mountains began to rise up, guarding the entrance to Glen Coe. It is a landscape so forbidding that when I pulled up at the Three Sisters viewpoint, I was genuinely relieved to see another couple, so I didn’t have to stand alone among the ominous peaks.

Scotland had stories, too: from the spruce and redwood trees planted in Glen Coe by Lord Strathcona in the 1890s to make his Canadian wife feel at home, to Queen Victoria taking the first ever fly-and-flop (train-and-flop, perhaps more accurately) at Blair Castle in 1844. Her visit was hosted by the 6th Duke of Atholl, who promised the security of his own private army (and who had to move out of his own castle during the royal stay). It was the beginning of a royal love affair with Scotland that led to the purchase of Balmoral in 1852.

When I got home from the long road trip – 13 days and 1,600 miles later – my husband took the same photograph of me perched on the car. It had been more of an adventure than I could have ever imagined – to lands unknown on the island I call home.

The Great Escape: Britain’s 400-Year Love Affair with Holidays by Annabelle Thorpe (£18.99, DK Red) is available now. To support the Guardian, buy a copy from guardianbookshop.com for £17.09