I did this and it was awesome! Buy some parchment paper at an office supplies store. Use a font on your computer that resembles caligraphy. Type a poem / letter expressing your love but don't address it to her specifically until the end. You can 'age' the letter by crumpling it a few times and then rolling it up. Start it like "Oh, how do I love thee? May this letter find you that you will know how much I love you" you know .....mushy stuff. Place the letter inside a wine bottle and have it stratigically placed on the beach at a certain time by someone so that she finds it. In my case, she found it and said "Oh, look a time capsule... some highschool kids must have done this". She opened it and read it and was blown away. At the end it said "(name) will you marry me". Blown away!! You could easily set this up with a staff member at a very specific time and have him/her place it on the shore in a specific place with the note in the bottle with a cork sealing it.
In my case she LOVED it and all of her friends thought it was amazing that I came up with that idea. Give it a whirl and if you do let me know how you make out.
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