Yep, it's not even August and already I'm thinking about what I'll be doing next summer.

I'm familiar with lots of week-long, large-group, supported camping rides in the US. I've done the Bon Ton Roulet (600 riders in the Finger Lakes region of NY); I've read about GOBA (3000 people in Ohio) and, at the extreme, RAGBRAI (10,000 people swarm through Iowa). The bikingbis website has a list of dozens of rides like this.

Is this purely a US phenomenon? Or are Canadian and European equivalents mentioned in some corner of the web I haven't yet discovered?

Thanks for your help!