I was halfway through the song when it happened. A lump in my throat, a tear in my eye, my voice rendered useless. Thankfully, the 250 other singers standing alongside me carried on, and Mozart's Lacrimosa reached its rousing climax.
That was almost a year ago, the moment when I realised just how phenomenal being part of something bigger can feel. It really hit me.
My emotional response was based on a number of factors. First, and rightly so, the absolute beauty of Mozart's music, sung by so many voices. But other layers added to the moment: the team effort (learning a four-part harmony is no walk in the park); the coming together of formerly disparate individuals; and the sense of our choir being more than the sum of its parts.
Tomorrow, on Friday 16 May, over 60,000 people in 24 countries will experience much the same thing. The Big Dance Pledge is a simple four-minute routine that anyone can learn. Then at 1pm and 7pm, local time, wherever you are, it will be performed en masse in public spaces around the world.
The idea behind the pledge is to promote dance participation; to encourage more people to discover the physical and mental benefits of creative movement. But why? What drives this desire to bring people together for cultural endeavour? For those who meet up on a regular basis – to sing songs, knit jumpers, paint landscapes, play concertos or perform plays – the answer is simple: it feels good.
For others, it's because re-creating the same experience at home is impossible (concertos for lone instruments being in such short supply). Some go simply to meet new people and make friends; and there are also those who see it as a way of learning and passing on skills.
There's the joy of sharing your achievements, and commiserating your less successful efforts. It's a genuine lifeline: the difference between spending hours at home alone or having a reason to go out. We know that being creative is good for our bodies and minds, and the same goes for being sociable – put the two together and you've got a formidable combination.
Through a happy coincidence, the Big Dance Pledge is taking place during Voluntary Arts Week, an annual celebration of amateur cultural participation that started in 2010. Countless other creative events will be taking place throughout the week, including the CraftBomb, where trees, park benches, school railings and other public places will be transformed by colourful creations created by people, together.
The feelgood factor that comes from joining forces with other people in your local community, to put a smile on the faces of those who happen upon your knitted flower, pom pom or bunting cannot be underestimated.
Across the Channel in Belgium, a similar event has been running for the past 19 years. The Week of Amateur Art is now a widely-recognised opportunity for people to come together creatively. Crucially, however, the Belgian equivalent of our local authorities and councils are heavily involved, helping to generate opportunities for people to take part.
As the organisation behind Voluntary Arts Week, we would like to see the same approach adopted in the UK and Ireland – to see more initiatives like the Big Dance Pledge, and for local government to recognise how and why the feelgood factor generated by cultural activity impacts on their residents; why it's worth investing both time and money in.
In St Albans, 20 different craft organisations have come together this week to decorate their town centre; in Yorkshire they're knitting bikes to celebrate the Tour de France; in Glasgow a locally-run arts venue is decorating a community garden with knitted chains. The list goes on, but it's not just the making that matters; it's the human contact. And not just for a week, but year-round.
Whether you're surrounded by 250 singers or a handful of knitters, the benefits of being part of a group are much the same. Hard to quantify perhaps, but impossible to ignore.
Kelly Donaldson is communications manager for Voluntary Arts – find out more about Voluntary Arts Week here or on Twitter @VolArtsWeek
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