Lisbon is about 2 and a half hours drive away from us Ally, up on the West Coast.
I love Lisbon
The buildings are lovely, the shops are also very good
transport is good (trams, tubes, buses) cheap and frequent. Just about every-one in the shops/restaurants speak some English.
If they're driving, then it would be a quick hop over the border to the Eastern Algarve, along the A22 or EN125, to Albuferia then up on the A2. Or take the IC1, which is just as good a road, still quiet but no tolls.
Or across, using the smaller, country roads above Mertola, onto Serpa, Beja and up that way.
Either way, they'd see some lovely countryside