There are many ways you can surprise your wife on your anniversary. Some ideas include:
Planning a romantic getaway to a place she's always wanted to visit
Planning a surprise party with friends and family
Cooking a special meal at home
Writing her a heartfelt love letter
Getting her a thoughtful and meaningful gift
Planning a special day filled with activities she enjoys
Make a memory book or album of your journey together.
Ultimately, the most important thing is that the surprise comes from the heart and shows her how much you love and appreciate her.