We don't know whether this is this or another of the evocative images in Italo Calvino's 'Invisible Cities'. But it is certain that something from these pages has influenced the project of Chemnitz, European Capital of Culture 2025. This invisible thread that brings out the happy city connects in Chemnitz the many points of a journey between past, present and future, between art and craft, between what was and what can be, between democracy and culture.

And happiness can be seen in the eyes of those who organise or take part in this journey to connect the dots of a difficult history, but one full of hope and confidence.

Such as in the eyes of Josephine Hage, director of the Makers, Business & Artsmaking project, through which the craftspeople of Chemnitz and the region seek to challenge the present with creativity, patience and community involvement. He accompanied us to the craft workshops of Schneeberg, a municipality of 16,042 inhabitants in Saxony, one of the 35 municipalities actively participating in the European Capital of Culture programme. Municipalities linked by a common thread to find a new destiny and to counteract the exodus of new generations, as is happening in every European heartland.

And how can one fail to read the hope and happiness in the eyes of Nils Bergauer, a manufacturer of handmade gloves, where everything is made with hands and for hands. Founded in the mid-1800s, he now exports his gloves all over the world, combining culture, tradition and modernity. Or the soothing happiness of the women in an art and sewing workshop, also in Schneeberg, where craftsmanship becomes a real window on the world.

Particularly in the textile sector, of which Chemnitz was truly the capital. This is demonstrated by the brand new museum dedicated to the Esche family, a textile company that was able to anticipate every technological evolution. To walk through these rooms in Chemnitz is to touch the entrepreneurial growth of a community, from the days of hand-spinning to the automatic reproduction of clothes.

In Chemnitz, before the Second World War razed it to the ground and the geopolitical limitations of East Germany held back its development, the first industrial revolution gave this community a European centre.

Today, a century after those adventures, a new industrial revolution is being attempted, based on the relationship between creativity, culture and democracy. This is one of the pillars of the Chemnitz 2025 cultural programme.

The creative impulse - indispensable for awakening and demonstrating happiness - is strong in the artistic journey that interleave community and territory. And therefore not only events, in the rich Chemnitz calendar, but also and above all the growth of skills to show what was invisible until yesterday.

After all, skills are the main infrastructure of a territory, much more than trains and roads.

We are still in Chemnitz, the heart of Saxony, the heart of former East Germany, where the largest bust in the world is dedicated to Karl Marx, who also had nothing to do with this place.

It is difficult to explain the reasons for this huge presence, a symbol of the city that for many years wanted to call itself "The City of Karl Marx" until, after the fall of the Berlin Wall, it became known as Chemnitz, after the river that runs through it.

And it is here that the need to have one's own small, tiny space for a variety of functions - archive, place of repair or production, space for artistic reaction, space for social exchange - has slowly stratified in the community.

There are 3,000 garages in Chemnitz. One of the main projects of Chemnitz European Capital of Culture 2025 is to upgrade these mini-places, trying to connect them like Calvino's invisible thread: community, needs, social innovation, sharing, artistic production. Then, in the summer, there will be a festival to reanimate these places, from individual to collective. The transition from 'I' to 'we' is fundamental for any cultural capital.

In Chemnitz, too, invisible threads connect the chimneys of the many factories that still exist, or have been abandoned or revived through art. In this way, energy is released not so much from the chimneys as from their coatings of murals, colours and graffiti.

A city in colour, like the cobalt blue that runs through the history and identity of this region.

Everything tries to be visible. Everything tries to make the invisible visible, the hidden visible, in a kind of thread that connects the points of a new horizon full of hope and happiness.

The future of Chemnitz hangs in the balance. The slogan plays on the letter C, both as the initial letter of Chemnitz and as its pronunciation (see). We see graphically a letter, but behind this letter a world is revealed (see). And so the Chemnitz project starts from this game between the visible and the invisible: C the invisible. Seeing the unseen. A way of inviting the community to go beyond schemes, prejudices, to look at what has not yet been seen.

A bit like works of art distributed along an original route.

It is called PURPLE PATH art and sculpture trail, another interesting project in the capital.

On this long and evocative journey, we saw the patinated bronze of the abstract sculpture Stack by Tony Cragg, born in 1949 in Liverpool, England and now living in Wuppertal, Germany, which evokes natural phenomena such as eroded rock, planed wood and volcanic plumes of smoke. The layered geometric shapes and silhouettes, which are replicated, rotated and expanded to create dynamic structures, are also reminiscent of geological models, digital data visualisations and reproductions of images from a scanning electron microscope. It is installed in the spa gardens of Aue-Bad Schlema. Or the pile of coins by painter and sculptor Sean Scully, born in Dublin, Ireland, in 1945. And installed only a few metres from the magnificent late-Gothic cathedral of St Wolfgang in Schneeberg.

Once again, the imaginary thread tries to weave between languages, places, communities, trying to make the light of a new day live and see with new intensity.

On this trip to the European Capital of Culture, we were also able to appreciate the staging of the opening ceremony. A huge stage built around the head of Karl Marx.

A truly beautiful and evocative idea. It was as if the city wanted to reclaim a past that was in a state of upheaval by putting a key figure in its history back in the spotlight. And the philosopher was there to see what was happening among the lights, the dances, the bandoneon and the great artists. To see what even he would never have seen. And that today the whole world is invited to see, to discover, to open up to a future of culture, creativity, community. And of happiness.

There will be much more to see in Chemnitz. To find out more, visit their website or follow EcocNews, which, as always, will select the most important events for you.