There is, really, nothing to see there. So, if you want to make a good picture of the Monastery's facade, that's a good point, otherwise there is no reason to justify the effort of climbing the steep way.
I know that there are some beautiful houses in the way, but you need not to go up to the top to see them.
In several places around Alcobaça you may see signs announcing Parreitas. It's a place where a friend of mine, about 40 years ago, discovered some roman ruins. I didn't visit the place with him, when excavations began, nor later. But a couple ot years ago I decided to go and have a look.
In the way between Alcobaça and Nazaré there's a sign, pointing to the direction where I knew the ruins are. I decided to follow the signs and... found nothing.
Last month, travelling in the area with Fernanda and a couple of local friends, I discovered that no one of them ever saw Parreitas, and once again, I followed the signs to find... nothing.
Searching in Google Earth I discovered that the ruins are some kilometers far from the expected place, without any indication after the one in Nazaré's road.
So, if you decide to go there you better forget the signs and try to find the way by yourself, but for what I have seen there's not much to see there. The only erected columns are in a roundabout at Alcobaça's entrance, without any clear indication of its origin.
Unique Suggestions: At last, I found it. Just a waste of time. excavations were only beginning and there's almost nothing to see.