Just past the Landhuis Santa Martha, near the town of Soto, is a hilly, forested patch of Curaçao which hasn't yet been developed. More accurately, I should say that it's no longer developed. We followed the road until reaching its end at Sunset Waters, a former resort which has been abandoned for years.
Watamula, at the northern tip of Curaçao, is a windblown wasteland of jagged volcanic rocks. It's not an area in which you'd want to spend a majority of your vacation, but it has a few geological features that are worth hunting down.