In the nineteenth century, thanks to its clear skies and rich patrons, the Côte d’Azur became a centre of astrological expertise. Just above Nice on Mont Gros, a Dutch banker built one of the world’s biggest refracting telescopes in 1879, complete with a dome engineered by Gustav Eiffel, but it soon became clear that, to really penetrate the deepest secrets of the heavens, it would have to move higher. So a new telescope was built, more than 2,700 metres up, near the summit of Mont Mouner in the vast wildernesses of the Alpes-Maritimes.

These days, the Nice backcountry is designated as a Dark Sky Reserve – a site of scientific research and a place that connects people to nature and our universal heritage of the night sky – so we decided to explore the connections between past and present in a stargazing, Star Chasing hike.

Starting in a car park above the small ski resort of Valberg, we had a long day ahead: 22 kilometres of hiking with 1,100 metres of vertical ascent, and the day was quickly heating up. The first hour or two passed through lushly wooded pastures and valleys, which gradually gave way to rocky cliffs, only the wind and the sound of our feet crunching through the gravel. By the time we stopped for lunch, in a recess out of the chilly wind, we were in a lunar landscape, and surrounded by first little patches of snow sitting dusty and subdued in the sun.

From there the path snaked up towards the summit ridge, a landscape of incomparable vastness beneath the blue dome of the sky, in which any human presence felt lost. Bald vultures circled overhead.

While the line to the top of Mont Mounier itself was along a wicked, sharp arête, the secondary summit of the Petit Mounier was wide and welcoming – a perfect place to build an observatory! – but still the scale of the undertaking was breathtaking. All materials were brought up the way that we’d walked, and the builder, a certain M. Maynard, also dug a water tank near the lodgings and the observatory, which was covered by a dome of tarred canvas.

Despite a fire destroying the buildings in 1893, Maynard lived on top of the mountain year for 25 years, through winters when there could be up to 5 metres of snow, taking scientific readings and welcoming visitors to stay. However, after World War 1 the telescope was abandoned. The site was just too difficult to maintain.

As we retraced our steps to head down the other side of the mountain towards our refuge for the night, gradually greenery and life returned to the grey mineral world of the summits. The perfume of flowers, butterflies… little things you’d miss if you spent years living on a mountaintop.

With another 13 kilometres to walk, we were almost late for dinner, but it was worth it watch the chamois and marmots at play in the magic hours before dusk. The welcome at the Refuge de Longon, at 1,880 metres above sea level, was special: home-made pine wine, lasagne with meat from the herd, and artisanal cheeses. Only accessible by foot (or donkey) via the famous GR5 long-distance path, the refuge was also a working dairy: 60 cows were due to arrive from the lowlands the week following our visit, for their summer residence in the premium high-altitude pastures.

After dinner we went outside to watch the stars, but the sky was shrouded in wraithlike clouds that masked the celestial lights. But as we lay on the tables looking up, certain constellations popped into prominence, a vast moving tapestry as the clouds shifted and the satellites and night flights passed silently above us. At the end of the valley, the silhouette of Mont Mounier stood guard.

The next morning, the aches and stiffness soon disappeared in the gentle sun and fresh air. The marmottes were still out to play and we stopped for an early lunch of cheese and saucisson next to a stream.

With much less climbing to do, it seemed to take no time to walk the 13 kilometres back to the car, skirting around the mountain rather than going right up it. But Mont Mounier was ever-present above our right shoulders, reminding us that although we may not be able to depend on cosmic revelations, the mountains will always be there.