Sorry if this has been answered; I did a couple of searches and could not find this topic.

We're into prime bike riding season. I ride my bike a lot and I see a lot of groups out there. Some groups I see ride single file and others ride "peloton" style. (That is, in ranks with several riders abreast in each row.) Fortunately for me, I'm much to slow to ride with any group I would assume that a couple of folks riding abreast on a country road are not breaking the law. But I can't find a confirmation of that. Does anyone have any insights into what is legal in this regard?

It's not illegal per se, but the Highway Traffic does require that you keep to the right when being overtaken by a faster vehicle.

148(6) - Every person on a bicycle or motor assisted bicycle who is overtaken by a vehicle or equestrian travelling at a greater speed shall turn out to the right and allow the vehicle or equestrian to pass and the vehicle or equestrian overtaking shall turn out to the left so far as may be necessary to avoid a collision

So basically it's fine if there's no traffic or you're riding on a roadway where cars can easily pass, but if you're staring to obstruct vehicles you need to pull to the right and ride single file.

You should also check local bylaws where you may be riding which may prohibit bicycles from riding two or more abreast.

Thank you, Stanton and Decatur.