Okay, so maybe it’s not a super big secret, but it’s a really nice view; two views actually. When walking back down the hill from the upper waterfalls you walk right past it (see the end for specific details on finding it).
Before turning right to get the above view, you could have continued straight and to the left a little (through the brush) and you can see north-east up the coast. From the spot you’re at, you won’t even see Montezuma, you’ll be looking right over it.
So as you come down the big hill, either from the upper waterfalls or from the Mariposario Butterfly Gardens, after you pass the private bridge to the really big house (you can’t miss it), keep your eyes to the right shoulder and about 50 yards (or 50 meters) past the bridge you’ll see the grass on the incline is a little worn (see picture) climb up there and head left.
When you get near the end on the right you’ll see south-west down the coast, towards Cabuya and Cabo Blanco; if you veer towards the left you’ll see north-east. It’s a really nice view in either direction! The north-east view is a little hidden, but just take a minute and you’ll find it.
There used to be fencing there so watch out for barbed wire. And keep in mind, it’s not a public park, so tread carefully…
UPDATE! This isn’t such a secret now and it looks like someone is going to start building (April 2011).