http://www.youtube.com/watch?v=xtWmXm9MuzU

Seen here. Such a great piece of music - and it's doing my nut in because I've heard it somewhere else on another episode soundtrack...

Can anyone kindly help? Thank you!

Its "The Wedding of River Song" from the Season 6 Soundtrack

http://www.youtube.com/watch?v=HOTgKA1CV74

Awesome work. Thank you.