Complex sentence: There are two main places where people gather to eat the grapes: with family after the dinner or in the main squares around the country, the Puerta del Sol in Madrid being the most famous place to do it.
Split into simpler sentences: There are two main places where people gather to take the grapes. With family after the dinner, or in the main squares around the country, the Puerta del Sol in Madrid being the most famous place to do it.