A great resource for finding unique cards for any occasion including anniversary cards is , all of these cards are unique and one of a kind since they are homemade by their sellers.
I think the most special and sentimental cards in the world always come from Hallmark you just have to spend time reading them to find the perfect one!
Hallmark has probably the widest selection of cards of any greeting card company. That said, if you check the lot of Hallmark anniversary cards and still don't find what you're looking for, what about making a personalized card, or having a card company personalize one for you?
Hallmark makes really romantic anniversary cards everyday. Honestly the most romantic anniversary cards are not make by a company they are made by you. You can put your personal experiences on the card and your significant other will see you actually spent time on it- that would be enough to win anyones heart.
Hallmark makes some very romantic cards. Of course the most romantic is one that you make or one that you write your own words into so that it is unique.
I can't think of the Company's name but it's a poets name. I think it's Emily Matthews, or something close to that. The cards are usually kind of like a poem, they are wordy but really express how you feel. The thing I like about her cards is that they are meaningful, like "I will love you until we're old"