3) Kuranda Range Road (aka Kennedy Hwy): About 14km
The start of this is about 15-20 minutes north of Cairns.
You'd be very lucky to get through this one unhindered by slow tourists in their Hyundai Getzs, the Tourist buses, or the tradies going up and down for work. If you DO get a free run, it's great. You get scenic rainforest and a windy road easily capable of high speeds (the speed limit is 80).
I've never gotten a completely free run with the MX5, but the one time I did, it was in my Nissan Pulsar, which was still fun, understeer and all. There's also a nice lookout halfway up.
2) The road to Port Douglas (aka Captain Cook Hwy): About 40km
The start of this drive is about 30 minutes north of Cairns.
This one has about the same or higher chance of getting a free run, but the average speed (of other drivers) is generally higher since the curves are less sharp, and a bit more straight roads. You get a nice ocean view for most of the drive though.
1) The Gillies Hwy (aka Gordonvale-Atherton Rd): About 17km
The start of this is about 30 minutes south of Cairns.
If you are graced with the luck of a free run (like I was today), you can have some amazing fun on this one. I was sitting in 2nd or 3rd almost the entire time, with some rare 4th gear on some of the small straights.
The roads are a little bumpier (for about half of it) than the other two so if you have ultra stiff suspension you might have to be a bit slower (we're talking a mountain range with much of it with no guardrails!), the same might be true of a wet day. Definitely a thrilling drive and I'll probably be doing it regularly.
If you start from Cairns and go towards Atherton, you could either turn around go back the other way, or head all the way past Atherton, turn before Mareeba and then also go down the Kuranda range Road. But the second option will take 2 hours including like 50km of straight roads.
All three of these have \"slow vehicle turnout\" points but it's random whether said slow drivers will use them. The slow-ass tour buses and tradesmen are probably least likely to use them. The speed limit is 80 on all these roads too, but most of the time other drivers will be going slower than this, depending on the road.
. I had the pleasure of being in Cairns earlier this year and was able to drive the roads mentioned above. They sure are good driving roads. Unfortunately, I was driving a Toyota Camry, but all I could think about when driving the roads was \"I wish I was in the MX5!\" 
