Before Berlin was so radically and comprehensively gentrified, I lived in a fourth floor apartment of a crumbling house whose windows looked across a concrete yard into an apartment of an old man. We largely kept different hours, and he to himself. As such, our exchanges never progressed beyond the occasional stairwell greeting.

But late at night I would often see the light go on in his kitchen, and in he would hobble. Until one evening, he didn't. For a couple of days, I rang his bell and eventually alerted the building's managers. They came and shortly thereafter confirmed my worst fears. He had died.

Elke Schilling, a silver-haired woman in her early 70s, had a similar experience in her block of flats. When she saw no sign of life from the neighboring apartment for a couple of weeks, she called the police. They would only break in on the condition that she paid for the repairs should the missing man be on holiday. Needless to say, he wasn't.

The incident proved impelling. Realizing the need to tackle isolation in this city of almost 4 million, she founded Silbernetz, a telephone-based solution modeled on a British project.

And for eight days over the Christmas period, she and her team offered Berlin's old and lonely something she describes as elementary: the chance to converse. Of the 300 calls, a third led to real conversations.

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That, coupled with the estimated 300,000 Berliners over the age of 60 who suffer from some degree of loneliness — often because a spouse and friends have died, family has moved away or they've had to downsize to a completely different part of the city — underscored Elke Schilling's determination to make the Silbernetz hotline a more permanent fixture.

That is now the goal.

Spreading the word is vital

Across town, music, prosecco and dance herald the opening of another new venture designed to prevent the onset of loneliness. A Humanist Association smorgasbord of cultural, social, linguistic and technical opportunities for the 60+ based on the idea of gemeinsam statt einsam or together rather than lonely.

And to underscore the richness of togetherness, a quartet of ladies in red accompanied by a solitary man on guitar perform a snippet from one of the plays they draw on their experiences to write. Their closing line, delivered with punch and passion, is a simple declaration of love for life.

As they see it, it's about getting maximum enjoyment out every phase and age of life, and being brave enough to try something new.

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For some, that might be singing and dancing, a computer course or a group walk in the park. For others, it might simply be picking up the telephone and dialing a number they know will connect them to someone who is happy to talk.

I have long since left the apartment building with the concrete yard, and now live in a place where everyone knows each other well enough to prevent the onset of isolation, but I often think of the old man who passed away at home alone. I'll never know, had there been the same opportunities back then that there are now, if the end of his life might have played out differently. But I do wonder.

In Berlin and beyond, British-born Tamsin Walker takes a closer look at some of the quirks and perks of life in Germany, which has been her home for almost 20 years. She tweets as @TamsinkateW