According to TMZ, "sources say the couple is set to swap "I Dos" at a castle in front of roughly 100 of their closest friends and family members.
We're told all guests will be asked to fork over their cell phones -- so no one can Snapchat, Instagram, Twitter, Tumblr, Facebook, Pinterest, Periscope or MySpace the event.
Our sources say the guests will meet at a central location -- and will be transported to the mystery wedding location ... to ensure privacy.
