In reply to chris_r:
Hi Chris
Just got back from climbing both Sintra and Cascais for a couple of days. Both are good fun and climbable at this time of year. Cascais is hotter, but (so long as it's not too rough) you can jump in the sea to cool off! We managed to do full days of climbing there on hot days, just belaying in the shade wherever possible.
Cascais is short(ish) limestone routes, although many (most?) are longer than at Portland. Rock is generally really good quality. Head to the lighthouse at Cascais, the entrance is the next path to the west. Once you're down at the crag, filter along east for some harder and less busy routes.
For sintra, use the www.gme... topo (above) which is pretty good (no need to buy the book if you're just doing these two sites - we didn't). The directions to the crag which we had were pretty awful - get a map (if necessary from tourist info), the parking bay is on Estrada da Pena, and you walk up the steps which are about 100m into the 'natural park' (which is just up from the parking bay).
The climbing at Sintra is pretty particular - exposed granite routes where you're often relying purely on friction - no real foot or handholds! That said, the two main multipitch routes are nice (New Wave and the three-pitch route slightly to the left of it, can't remember the name). Take a jumper in case it's cloudy, and sunscreen in case it's not - belaying up on the routes can get quite hot.
Have fun, email me if you'd like to know more
Joe
PS for a non-climbing day, the capuchin convent at sintra is pretty cool!