Call them what you will.
They are always noisy, always start later that they are publicized and are often very difficult to understand. You may see a poster advertising a Feira in your local town or village.
Firstly just because music is playing don’t think that anyone but the sound guy or DJ will be there. They are probably just testing the PA system.
Add around 45 minute to an hour onto any times that you see published.
A good idea is to take a digital photograph of any posters that catch your eye so that you can take the image home to translate at your leisure.
Some of the smallest festas have the more simple traditional games for children and are fun to watch. Others have lighthearted auctions of home made produce, cakes, wine, sausages, cheese for example.
The purpose of the festas and feiras is to make a little money to support the church or local community hall. They are all religiously linked. For instance this poster if for the Fair of St Miguel.
There are often grilled sardines on offer or grilled pork and locally produced wine.
Very often they are at their liveliest late at nigh on a Sunday when its nice and cool for dancing. Although far to late for us!
If you are going to a fiesta don’t be afraid to join in and enjoy yourselves. (local tip) In rural areas it is frowned upon for women to drink out of bottles.
It always amazes me how welcoming people are it could just be traditional hospitality and its a very good way to meet people from your village or town