Since we didn't make advance reservations we took the 2-hour private sailing adventure since that was all that was available.   We enjoyed this so much, we went again when my sister from Santa Fe visited the next year.  The yacht can hold up to six people and costs about $349.  It includes a glass of wine per person and a selection of cheese, fruit, and sodas.  However, you can bring your own on board.  So we usually bring pre-mixed drinks and a bottle or two of wine depending on how many people are going.  We met Captain Curtis on Harbor Island near the Sheraton Hotel. Once we were onboard and settled, we slowly pulled away from the marina.  Captain Curtis asked us if we wanted to head south toward downtown or north toward Point Loma.  I've done both directions.  If you are on a longer cruise I would recommend going north so you can head out to the tip of Point Loma and into the ocean.  There you might see whales and other sea life.  If it is a shorter tour, then head south toward downtown Coronado for some great views.  The first time we went, we saw quite a few seals and sea lions.  And the second time, brought us an extraordinary view of San Diego skyline and shipping vessels while relaxing with friends and family.  If there is one thing I've learned from both of these trips is that it is never long enough.  Next time, I'd like to get a bigger group of people and take full day or half day adventure.