My son, who is active duty navy stationed at North Island, and I took a 5:30 pm North harbor tour. We thoroughly enjoyed it. Even though there were many people on board, we had plenty of distance from others. The tour guide was very knowledgeable and I especially enjoyed all the information given. Even when he was discussing the base and specifics about it I looked at my son to see if the information was accurate. My son shook his head yes in affirmation. The cost is VERY reasonable. I would highly recommend this tour.