I travelled to this hidden Japanese haven where Tokyoites go to slow down

It's a special kind of quiet. It's not something you hear, it's a feeling, a settling, a rest. In Tochigi prefecture's mountainous hidden gem, I stuck out like a tall, loud-mouthed Australian sore thumb. I am the antithesis of serenity, the enemy of calm and by all accounts move like a bull in a China shop.

Tokyo's madness felt native, but a few days in Japan's Nasu Highlands would prove to be exactly what I needed. As I left the metropolis where multi-storey buildings butted up against each other and children played baseball on fields wedged between the river and the highway, the mania outside was slowly replaced with stunning red and orange hues.

We met with our guide, Tetsuya, chief executive of Ride Experience who, like many other former Tokyoites, had come to understand what the Japanese royal family recognised almost a century ago. Nasu is pure magic. It is the place to unwind.

But not before lunch.

Stop at any local soba spot, slip off your shoes and take a seat at a sunken table. Much to my delight, slurping your noodles loudly is considered a compliment to the chef. Full to the brim with one steaming delight, it only makes sense to go on to the next. Japan is known for its Shinto shrines, both places of worship and dwellings of the "kami", the Shinto "gods". Perched on the top of a hill overlooking a winding path through a valley is the Nasu Yuzen Shrine. It enshrines the god of onsen, a natural hot spring mineral bath believed to bring health benefits to the body and mind. For many Japanese people, a soak in the steaming hot pools is an almost daily practice.

The Shikanoyu hot spring at the Nasu Yuzen Shrine is the oldest in the Tochigi prefecture, with about 1390 years of history. I needed to take a peek. Asking to enter an onsen - where the Japanese traditionally bathe nude - "just for a squiz" was a very unusual request but the manager kindly obliged. My brash naivety combined with the polite nature of the Japanese saw me standing, fully clothed, in a room full of women simply minding their own business.

And so, I ticked that one off the bucket list. Having committed my first cultural bungle within 48 hours of landing in Japan, it was time to retreat for some much-needed R&R (rest and reflection).

Sansuikaku was the answer to my prayers. A Nasu ryokan (inn) is truly something else. Under a high, rounded ceiling, with a traditional wooden floor underfoot, it felt like I had stepped into another world. The constant flow of water from the private onsen on my balcony was an invitation I could not resist. As whispers of steam furled around me, in a stillness I have never felt before, I exhaled the usual flurry of thoughts, tensions and to-do lists. I could get used to this.

After a quick rinse, sitting on a wooden stool in the shower, I wrapped myself in a yukata (a cotton kimono) and headed to the private dining room for my first kaiseki experience. Each course was more delicate and precise than the last. The freshest sashimi. Paper-thin Waygu beef cooked in a copper bowl of soy milk over the flame of a candle. Tender mushrooms. Exquisite flavours washed down with sake sipped from a hand-crafted ceramic cup not much bigger than a thimble.

Everyone needs to try this once. I was lucky enough to try it twice.

The best way to see Nasu, truly see it, is with an e-bike and someone armed with local knowledge. Let Tetsuya and his team lead you through stunning forests, past rice fields that descend like stairs through the valley and reward yourself with a soba-flavoured ice-cream.

Stop to walk through the bamboo forest where trees stretch storeys high, whiz past farming plains before being welcomed into a local farmer's house for a home-cooked lunch. Yoko, her mother Kazuko and father Makoto made us feel right at home.

Local farmers have long used shino bamboo grown in the highlands for sieves, baskets and agricultural tools. After lunch, we watched as a craftswoman used her teeth to split the bamboo into thin strips, called hine, before weaving it into something else entirely. I tried it myself. There's a reason it takes many years to master the technique.

After working up an appetite, dinner at the tiny, hole-in-the-wall sushi restaurant Tamaru-Ken was a welcome remedy. Nasu already feels unreal, but leaving the restaurant to a flurry of snow was the perfect nightcap. I've never really been one with nature, but in Nasu, something within me had started to shift. I began to appreciate its beauty, the depth of its silence, its calm.

It is here I learn my favourite Japanese word after my second cultural bungle - asking for kewpie mayo on the side.

I am a "mayola", a self-confessed lover of mayo, and I wear the moniker like a badge of honour.

The Nasu Heisei-no-Mori forest was almost never entered by people until recent years due to its previous status as Nasu Imperial Villa land. Our guide, Yukari, is the most positive person I have ever met. As we scramble down a mountainside with colourful leaf litter underfoot, she stops to hug a tree. Knowledgeable, kind and enthusiastic, Kari has me enraptured by acorns and Nikko maple. Her love of nature is contagious. When she pulls a thermos of hot coffee out of her backpack and invites us to sit, sip and bathe in the forest, I like her even more.

One of my favourite things to do in a new country is to check out the local grocery shop.

If you haven't yet had your fill of nature's wonders, see the spectacular crimson trees at Shiobara as a warm-up for Ryuokyo Gorge in Nikko, where a river carves its way through the volcanic rock canyon. Ride an e-bike through the 37-kilometre Namiki Cedar Avenue, the longest tree-lined road in the world, hemmed by cedar trees which stand like feudal lords who traversed the same path some 400 years ago.

Crack open a barrel at the Tonoike Sake Brewery, see the Higeta Indigo Dyeing Studio where linens turn "Japan Blue" in 72 earthenware indigo vats. Wander through the Nikko World Heritage-listed shrine.

Do it all, but do it slowly. This is mindful travel.

The writer was a guest of Nasu, Tochigi prefecture