What's the collective noun for Mayors?

Because whatever it is that's what was happening down in Islington today.

My curiosity was first aroused by a couple of pipers in full knife-down-the-sock regalia wandering up Upper Street, a few minutes later I could hear the pipes and when I got round the corner there they were piping a tribute to the massed ranks in their fur trimmed robes who were gathered in the pub!

They were then piped across the main road to congregate on the Town Hall steps!

I don't know what on earth was happening, obviously strange things go on when they think we're all still sleeping off the missing hour!