Translation:We celebrate carnival in the southern part of the Netherlands.
In the US, "Carnival" is called "Mardi Gras", and it's usually celebrated in the state of Louisiana. A "carnival" is usually made up of traveling amusement rides, vendors, games and acts. This seems to be closer to the Dutch word "kermis". A "fair" is typically a gathering of people to display or trade produce and animals, and may or may not have a travelling carnival associated with it. Thus "fair" translates to the Dutch word "jaarmarkt".
Upon Googling 'carnaval Nederland', it looks to me like what I would call a carnival, here in the UK.
Eindhoven grinds to a halt during Carnaval which is the big blow out before Lent but religion is not a big thing anymore down south but the merrymaking traditions remain. Yes loads of people young and old dress up and participate singing drinking dancing drinking for about a week. There is also a parade with floats and those people take it very seriously. It is a lot of fun.