Europeans really know how to do Christmas. Because they don't have Thanksgiving, I feel like Christmas decorations and preparations are way more hardcore here than they are in the states. They don't have to focus their energy on two holidays — it's all in for the big one.
One of the most unique things that happen in various towns across Europe, especially in Germanic areas like Germany, Austria and northern Italy, are the Christmas markets. In Italy they are called mercatino di Natale, and in Germany, Christkindlmarkt. Regular markets are a common place to get groceries and household goods here, but the Christmas markets are a special festive thing — and only made better with glühwein.