I found this code in a Rails cookbook.

class BlogController < ApplicationController

def display_by_date
 year = params[:year]
 month = params[:month]
 day = params[:day]
 day ='0'+day if day && day.size == 1
 @day = day
 if ( year && month && day )
  render(:template => "blog/#{year}/#{month}/#{day}")
 elsif ( year )
  render(:template => "blog/#{year}/list")
 end
end

end

I'm not sure what to name the templates so the router can find them. Thanks for your help.