Here is a photo from my “archives”, of the sanctuary of the Cathedral of St. John the Baptist in Trnava, Slovakia (large-ish city near the capital city of Bratislava).
Locals claim that the high altar, made of wood, is one of the largest of its kind in Europe. It is about 67 feet tall. Click to enlarge the image.
Altars like this, covered in images of saints and symbols of the faith, give us a visual aid for our prayer and a certain access to unseen realities that we simply do not have in so many of our modern churches. The art serves and supports the faith and the liturgy, adding a new dimension to our worship and to our experience of God.