Planning a unique birthday celebration for your husband involves thinking about his interests and hobbies. Consider arranging a surprise adventure like a hot air balloon ride, a scenic helicopter tour, or a day of sports activities he enjoys. For a touch of nostalgia, organize a surprise visit to a place with sentimental value, such as where you first met or had a memorable date. Personalized gifts like a custom-made piece of art or a monogrammed item can add a thoughtful touch. Planning a romantic dinner at home or a weekend getaway to a cozy cabin can also create cherished memories. Ultimately, the key is to choose something that aligns with his passions and shows that you know him well.