What is the regatta? How do I take part?

The Regatta is a tournament in which Neighborhoods compete for rewards. It's held several times a month. Players can access the regatta at level 15, provided they have built the Neighborhood house and the yacht club and joined a Neighborhood. Players in any Neighborhood can join the regatta when it starts, provided that they have not quit a Neighborhood during the current regatta. If they have, then the player must miss one week of the regatta as a penalty.