The same information can be found at:
https://sites.google.com/site/shoheisoahutips/free-parking-at-fort-derussy-beach-park
Fort Derussy Beach Park is one of my favorite beaches in Honolulu. I think it's better than Waikiki because it's less crowded, it's dog friendly, and there are just as many activities to do with convenient shops right along the beach. This beach often gets overlooked because it's in between Ala Moana Beach Park and Waikiki, but it's definitely worth checking out because it's a beautiful beach. There is a reason why Hilton Hawaiian Village is located right there near Fort Derussy.
The problem is parking. It's there, but it's very expensive. I was shelling out quarters for street parking on Saratoga Rd. OK, so you're rich, and you don't mind, but there are like 10 spaces to accommodate 100 people wanting to get to the beach. If you're lucky, or you go early in the morning on the weekdays, you might find a space open.
Another parking spot is the military parking along Kalia Rd, which is open to the public as well, but this is very expensive as well. Military personnel get something like a dollar discount per hour so it's 3 bucks an hour for parking instead of 4. You figure if you lay your life on the line for your country, the parking is going to be free, but what do I know.
There is also a parking structure across the street from the Hale Koa Hotel. It's just as expensive as the military parking. See the map below for clarification:
Here's where you should park:
To get there, you should take Kalakaua in to Waikiki, then make a right on Ala Moana Blvd, and a left on Kahanamoku St, right before the Ilikai Hotel. Keep going on Kahanamoku, and take a left at the end of the street. Keep going for a while, and then park at the lot located on the left at the end of the street or at the harbor. You can also google Duke Kahanamoku Lagoon and get google map directions there.
Once you are there, be careful and read the signs because there are deceptive parking areas that are PAID parking, intermingled with the free parking, and you do not want to get ticketed, or worse, towed.
So, the free parking takes you on the other side of the beach, but it's a short walk to the park, and you get to see all of the fancy hotels and their beach side restaurants and bars as you walk along. Oh, there's the beautiful beach too. Now you can come here every day without worrying about paying for parking!
Sunset at Fort Derussy Beach Park