Let your girlfriend know that you cherish the time that you spend together by giving her pictures of special moments. Try putting a picture of the two of you in a frame with the words "Happy Birthday" engraved, or if you are very serious, try a frame with the words "I Love You" engraved. If you are unable to pick just one photo, try a collage frame in which you can insert multiple pictures of the both of you, or order a whole album of pictures through an online photograph store such as Snapfish or Shutterfly.

Allow your girlfriend to show off a token of your love by purchasing jewelry for her 27th birthday. Try a heart necklace or a charm bracelet with a heart charm. For a more personalized gift, buy an engraved necklace or bracelet with a message such as "I love you" or "Happy 27th Birthday Sweetie!" If you are looking for an extravagant gift, a pair of diamond earrings are always classy.

A romantic weekend getaway is a perfect way to celebrate a birthday and plan alone time with your girlfriend. Find a romantic place and be sure to plan at least one romantic dinner and one couple's activity such as a couple's massage. If you are surprising her, be sure to check her calendar beforehand so that you can be certain that she will be free that weekend.

Purchase two tickets to a show for you and your girlfriend to celebrate this special occasion. If you do not have access to Broadway shows, try calling local colleges or theaters to see what type of shows they are offering. Don't forget to make reservations for a special dinner before or after the show.