There are many beautiful and unexpected moments that can occur at a wedding. Here are a few examples:

A beautiful sunset: If the wedding ceremony takes place outdoors, a beautiful sunset can provide a stunning backdrop for the ceremony and create a romantic atmosphere.
A heartfelt speech: A well-written and heartfelt speech from a family member or friend can be a very emotional and touching moment for the couple and their guests.
A surprise performance: A surprise performance, such as a dance or musical performance, can add a special touch to the wedding and be a memorable moment for the couple and their guests.
A meaningful ritual: Incorporating a meaningful ritual, such as a unity candle or sand ceremony, into the ceremony can add a unique and personal touch to the wedding.
A meaningful reading: Choosing a meaningful reading or poem to be read during the ceremony can add depth and emotion to the occasion.
A surprise guest: Seeing a loved one who was not expected to be at the wedding can be a wonderful surprise for the couple and their guests.

Overall, the most beautiful and unexpected moments at a wedding are often those that are personal and meaningful to the couple, and that add an element of surprise and emotion to the occasion.