This Sunday is Sing4Water, part of the Thames Festival. It takes place at The Scoop amphitheatre next to City Hall, London Bridge/Tower Hill tubes.
It's basically a mass choir of approx 600 people, all singing beautiful songs in harmony. There will also be some performances by professional a capella groups which have been mindblowing in previous years. Really uplifting to hear such beautiful sounds just from the human body. FREE FREE FREE! Although buckets will be going round collecting for WaterAid charity.
Anyone on Mumsnet Local for the area might also want to stick the event there and get an entry into this week's comp .