There are a number of very nice parks around the Big Island of Hawaii. It would be impossible to cover all of them, so this is just a short overview of a handful that I have visited over the course of my ten years of coming here.
Lava Tree State Park
Highway 132, south of Hilo
Near Pahoa, Puna Region
As with most of the region around Hilo, this is a very dense forest with a lot of thick brush and large trees. Lava Tree State Park is a preserved area that shows you what happens to the trees after lava runs through a forest. The lava coats the trees, and when the tree dies from within, the hollow "lava tree" is formed. This area had a lot of very fragile ground and huge gashes in the ground where the lava erupted. This volcanic activity took place in 1790. If you get out and walk around, be sure to stay on the path, and don't venture into the unmarked breaks in the earth. There are warning signs throughout the park to be careful walking due to the deep crevices in the ground.
There are limited restroom facilities here, but they were frankly too scuzzy for me to consider using. There really isn’t a lot to do or see here, allow yourself about 40-45 minutes to fully explore the area here.
To get to Lava Tree Park you will need to take Hwy. 11 south of Hilo (or heading towards Hilo if you are coming from Kona). Turn right on Hwy. 130 and proceed on to Hwy. 132.
Akaka Falls State Parks
10 miles north of Hilo
The bamboo forest is thick and wet, almost like a continual mist upon you. (Take bug repellent!) There wasn't much wildlife and only a few birds but the plants and flowers were beautiful. I saw my first Bird of Paradise flower in the wild here! I also saw bamboo stalks that had to have been at least three or even four inches thick.
For those who are unable to walk long distances or over steep grades, take the shorter path (to the left) towards the Akaka Falls. The hike is about 15 minutes each way and provides for a good view of the tallest of the falls in this park. That will lead you to the taller of the waterfalls here in Akaka Falls State Park. You can't get very close to it, but the view point gives you a wonderful photo op of the spectacular 400+ foot waterfall. The other path is a bit longer and more rugged a hike. It leads to the Kuhuna Falls via the circle route. The full loop path is about one-half mile.
This was a very well maintained state park, which had very nice restrooms, drinking water fountains and a picnic area. For us this was an hour stop on our road trip to Hilo. The detour was well worth the trip!
Hwy 19, approx. 30 miles north of Hilo
This is a very impressive county park, serving two purposes . . . one to provide locals and visitors with a nice location for picnics, barbeques and outdoor activities . . . but perhaps more important for those who live in the area, a loving tribute to the 24 who lost their lives in the April 1946 tsunami.
There is a memorial listing each of the school children and adults who were swept away, along with a nice historical archive of newspaper articles to include published interviews with a survivor who lived out on the ocean until she was rescued.
The park itself has a really nice picnic pavilion as well as grills, showers, restrooms and plenty of parking space. There is also an area to overnight camp here. This is not a good spot to go for the beach however, unless watching the ocean is mesmerizing and a photographic adventure that is of interest to you. The surf here at the point is very strong and there is no entry area for swimmers or surfers.
Keokea Beach Park
Hwy 270, near mile marker 27
This is another nice county park for being close to the ocean and watching the waves. Here the surf is accessible so you will likely see surfers hanging ten on the huge waves.
While this is strictly a day-use park, they do have a small picnic shelter that sits high up overlooking the ocean. There are also several porta potties (apparently the regular restrooms are currently out of service) and fresh water showers.
It is not recommended that you attempt swimming here, although there is a small inlet that is fed from the incoming ocean surge that seems pretty protected from the direct waves and undertow. I have seen families in this small area allowing the little ones to splash around in about a foot or two of water.
This is a park that like so many in Hawaii, I would not leave valuables in my car or go too far that the car is out of my sight. Often there are several locals hanging out here, drinking beer and having a good time. I would hate to return to my rental car to find the windows smashed and my stuff gone.
Punalu'u Beach Park
Hwy 11, approximately the 55 mile marker
South of Punalu'lu
OK saving one of the best for last . . . this is where you must go to have the best chance of seeing honu (turtles) on the beach or ride the surf in or out from shore. I've only "missed" once in ten years! (Sorry Cathy!)
This is also the most accessible black sand beach on the Big Island. While I suppose you could lay out here to take in the rays, you will probably find the continual pace of visitors walking by to be a bit of an annoyance. All of the Circle Island Tour buses stop here, so that will give you some idea of the foot traffic.
There is an area where you can picnic and there are camping permits available for those who wish to overnight here. The bathrooms are very nice and clean, making this a good spot to stop if you're traveling between Kona and Volcanoes Nat'l Park and/or Hilo.
There are so many more great parks, so for now I will post this link to the Hawaii County Parks website with a site map with links to each of their parks: http://www.co.hawaii.hi.us/parks/parks.htm and to the Hawaii State Parks website: http://www.stateparks.com/ranger-scripts/states.asp .