The only thing to watch out for are the kids on bikes who all think they are Valentino Rossi. Mind you, coming around a corner on the wrong side of the road and being face to face with a two tonne Range Rover soon slows them down a bit.
Antipolo itself was a bit of a pain coming back due to traffic but other than that, it was a very pleasant run out.
Pls disregard my post, saw in google earth it's a well paved mountain hiway leading to Infanta Quezon. Been to Infanta but uses the other route Famy Twisty rooad.
Last I heard there was a landslide and you can't go straight to Infanta due to a fallen/damaged bridge. You can still proceed to Jariel's and a few meter down the road is a water falls. But this was also damaged.
Jariel's Peak is pretty straightforward. Take Marcos Highway, go straight at the Masinag intersection, go past Cogeo, then up to Tanay. This is where the road becomes fun because of the winding mountain roads where you can enjoy your car's handling.
Once you get to the intersection of Sampaloc, Tanay (there is an ex-Shell station here which is the usual landmark), keep going straight until you reach Jariel's Peak.
Last time I went, there was about 50m of unpaved (but passable) road. Not sure if it's all cemented by now.