I always liked the serene opening to the 1812 Overture better than the finale. I wish I could have made a better ending for it than just a fade out, but whatever.
This portion of the overture is actually called "Troparion of the Holy Cross," or "O Lord Save Thy People," which is a traditional hymn in the Byzantine Church. Here is a link to a really good choir version:
https://youtu.be/LyRcvjto300
The clips I use are from Terrence Malick's film Tree of Life and stock footage. I don't own the clips or the song (obviously).