Visiting Japan, I realised how terribly little I knew about the country. Beyond the sushi, the origami, the Nissan cars and the geisha girls that we can all name is a land that never ceases to surprise. I never knew, for example, that there are 6,800 islands, and more than 100 active volcanoes; that the country is so spotless, you could eat your food off pretty much anything; that those old Japanese paintings of mountains and pine trees and deep valleys, which I always presumed were works of fiction, are almost photographic representations of this stunningly beautiful country.

A lot of people had told me that I’d find the Japanese a bit standoffish. But they were so incredibly welcoming and kind. They have such a precise way of doing things, and the ceremonies and courtesies bring you up short; you begin to wonder whether we haven’t become a bit rude in the West. These little courtesies oil the wheels of daily life so well: to wrap anything you buy in a shop, even if it’s just a pound of dates, so beautifully, then hand it to you with a small bow, it sort of makes the day great.

Follow Joanna’s fabulous tour of Japan

Here are five of my favourite experiences from this unforgettable country.

See the cranes in Hokkaido
Hokkaido — Japan’s northernmost and second largest island — is wonderfully peaceful and rural. And existing only in two or three tiny patches in the east are the fabled red-crowned cranes. I never thought I would actually see these birds: they’d taken on almost unicorn proportions in my mind, given how rare they are, how endangered, and how fleetingly they’re here every year. We stayed at the Hickory Wind Wilderness Lodge and rose early with our guide, Makoto, to trek to the nearby river.

There were no guarantees that the birds would be there, but to Makoto’s delight, they emerged through the misty morning light, standing tall, and there was such an array of them. It was like walking into the Garden of Eden. They’re so elegant — and they dance for each other. It was moving to watch. The bird has a totemic role in Japanese society. A few years ago, Japan Airlines dropped the crane from its livery and the airline’s fortunes went down. It ended up reinstating it.

Cranes flying in formation.

Land of the rising moon: red-crested cranes fly in formation above Hokkaido

GRANT FAINT/GETTY

Hike the Nakasendo way
With our tight filming schedule, I was only able to dip into this magical trail, but I would have loved to walk the entire 332-mile route. It stretches between Kyoto and what was once Edo (now Tokyo), and was one of the five routes nominated for use by the ruling shogun. Forcing troublesome barons to walk this colossal trail several times a year, taxing them as they went, was a way to keep them in line.

The trail is much as it was, with spectacular views and stretches of bamboo forest, and it’s beautifully kept. There are signposts showing mileage, and lovely little teashops where you can rest up and buy souvenirs such as slivers of the cedar wood that only grows here. Each stop on the way has its own stamp that you put into a book. It’s “puff, pant” challenging in places, but never less than gorgeous. Plus, you’re unlikely to see a single other westerner. It’s one of the world’s great “unwalked” trails.

Cherry Blossom In Full Bloom In Kyoto

Inspiring: cherry blossom lines the canals in Kyoto

BUDDHIKA WEERASINGHE/GETTY

See the cherry blossom in Kyoto
How reverently and excitedly the Japanese greet the coming of the cherry blossom is inspiring. How it will come, when it will come, which trees will come out first — these are matters of national importance. When it arrives in Kyoto — typically, late March to mid-April — it’s like a national celebration. Businessmen come down from their offices and loosen their ties, people picnic beneath it, and everywhere it falls like confetti. It’s thrilling.

We were talking to an old man who had given his life over to cherry trees; he showed me his beloved specimens as if he was showing off a collection of Rembrandts. You must do the Philosopher’s Walk, a path along a cherry-tree-lined canal, so called because of the professors and academics who used to muse and form their thoughts while walking there. The way that human life is mirrored in the flourishing, then withering, of the blossom is all part of the symbolism. As the West turns its eyes away from nature, Japan has kept it at the heart of its philosophy.

Explore the streets of Tokyo
I took a helicopter tour above the city and the buildings never seemed to stop. If you take the metropolitan area as a whole, there are 38m people here, the largest urban concentration on earth. Yet somehow that Japanese courtesy still prevails. You have to walk across the famous intersection outside Shibuya station — it’s a bit like the Abbey Road thing in London, only much, much busier. An estimated 800,000 people a day cross it. Watching it from my hotel room above, it was like the tide coming in and out.

All around here are malls and boutiques and buildings lit up with neon. But make sure you head down the side alleys, as that’s where you’ll find truly sensational food. It is beautifully presented, tastes wonderful and will keep you fit, fit, fit. It’s the healthiest diet in the world. In some of the backstreet restaurants, we had to take our shoes off and sit on the ground. (Some, kindly, dig little trenches for the less flexible foreigners.) At others, we’d be at a table. My favourite dishes were the miso soups. A great intimidating vase of it would be placed in front of you — and 10 minutes later, it would be empty.

Joanna at the 10th-century Mount Haguro pagoda, in northern Honshu

Joanna at the 10th-century Mount Haguro pagoda, in northern Honshu

Reflect in Nagasaki
When the atomic bomb was dropped on Nagasaki on August 9, 1945, the destruction of the city was almost absolute. Not that you’d know it today. It’s one of the most beautiful cities you can imagine, with a harbour and a mass of inlets — a little bit like Sydney. It’s a bright place, built out of the ashes, and the people are striking in their determination to look forward and not back.

But there are reminders. I visited Shiroyama Elementary School, which lost 1,400 of its 1,700 pupils that day. A tiny part of the school that wasn’t destroyed — a stairwell — has been turned into a little museum, and here I met a hibakusha, or survivor, who happened to be digging a shelter at his grandmother’s house when the blast hit. At the school is a small statue of a schoolboy with a dove on his elbow. Every child bows to this as they pass, like altar boys in a cathedral. This, and the fact that the city seems to have no bitterness despite the horrors visited upon it, touched me terribly. It’s a profoundly moving place.

Joanna was talking to Duncan Craig. Joanna Lumley’s Japan begins on ITV on Friday at 9pm

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