When I was on the Big Island in the summer of 2013, I saw that construction is nearing completion on the realignment, widening, and general modernization of the famous - formerly notorious - Saddle Road.
In years past, Saddle Road was infamous for being narrow, winding, dangerous, poorly lit, and pitted with potholes. Rental Car companies expressly forbade visitors to the Island from taking their vehicles on the road!
All this has change. The State of Hawaii has been committed to a lengthy, expensive, and challenging re-built of this important road. Most of it - all except about ten miles on the far western end - was finished when I was there. It provided a modern highway that lived up to standards that you would expect to find anywhere in the foothills or mountain approaches of Colorado or California. Only the far western end of the Saddle Road was still something that your grandparents might have driven over in the 1940s.
Chances are that you've looked at a map of the Big Island and thought: Hmmm...the Saddle Road looks like a short and scenic way to get from Hilo to the Kona side (or vice-versa). And it can be. Cutting through the lava-strewn saddle between Mauna Loa and Mauna Kea, it is definitely the shortest path between Hilo and Waimea. On the sunny morning I drove it, I caught a view of snow-covered Mauna Kea, dotted with observatories, as it played hide-and-seek through the clouds. The barren landscape was pocked with cinder cones and Mauna Loa rose boldly to my left. It was a great drive!
However, exercise caution. First and foremost, realize that most rent-a-car companies FORBID you to drive on the Saddle Road. If you damage your car there, you should lie about it unless the vehicle's undriveable or requires a police report -- then you're screwed and your insurance will probably be void. The one company that I know of that allows this, Harper's, is expensive but worth it if you want to drive this road (or head to the peak of Mauna Kea). The Saddle Road is windy and narrow in spots, and the blankets of fog that settle on it are so thick that you cannot see two median reflectors in front of you (I know -- this is what I experienced in the afternoon return trip). And locals recommend staying off it after dark -- and there's no scenary then any way.
We had a great time on this day long bus tour of the volcanoes. There was coffee, chocolate, taro bread macadamia nut and brittle tastings along the way. There were beautiful sights to see. I particularly liked the steam vent - a giant hole in the ground that steam streams out of. The tour guide was excellent (look out for him - Lincoln) and very helpful, he even dropped us off right outside the grocery store so we could get dinner.
A great day, well worth it but disappointed that we didn't see any molten lava.
We drove from Kalaoa to Hilo and had some breathtaking views at lava fields, the "Saddle" and Mauna Kea volcanoe. Although it was a hell of a ride we were glad to have witnessed it!
The state has plans to relign and improve Saddle Road in the near future. They want to make this road the vital link between east and west Hawaii. It's supposed to upgrade into a two-lane highway. Finally it should make the road less "exiting" and definately more rental-car friendly.
The road was built during WW II to provide access to an Army training area in the Big Island's interior. We had the feeling that it hasn't been maintained or improved much since. Although paved for its entire length, Saddle Road is a narrow, winding, barely two-lane road with steep grades, sharp curves, poor pavement conditions, inadequate signing and substandard drainage. Not surprisingly, Saddle Road has a higher accident rate compared with average roads.
Still you must consider that it is the shortest route between the east and the west side of the island. Despite its poor condition it is much used by island residents and a limited number of sightseers.
Saddle Road (State Route 200), the closest thing to a cross-island highway on the Big Island, is a famously bad road despised by most rental car companies. These companies generally prohibit tourists from taking their vehicles on the road. We were driven by locals at our day of departure and witnessed why it's unsafe to drive.
The road was built during WW II to provide access to an Army training area in the Big Island's interior. We had the feeling that it hasn't been maintained or improved much since.