Sister-ships Diamond Princess and Sapphire Princess include all the features traditionally enjoyed on Princess Grand-class vessels -- but with a twist. The two 116,000-ton ships are larger than their Grand-class fleetmates yet carry fewer passengers relative to their size. As a result, Diamond Princess and Sapphire Princess have a higher ratio of space per person and feel much roomier. Their exterior profiles are also sleeker, due to the repositioning of the high-in-the-sky disco to a spot on the uppermost deck. Facing aft, another disco improvement is the addition of an outside balcony overlooking the ship stern; this is a perfect spot for romantic stargazing.