Haha! Evil huh? I thoroughly recommend a few days in Evora, its a lovely town in itself (world heritage site) and has such fantastic megaliths in close proximity. I'm serioulsy considering a return trip in the next few months since there was so much I didn't see further north and to the south east, particularly Crato dolmen which has red paint still visible inside it according to Cope, how fantastic is that! The hire car only cost €16 a day (£10!) with Budget so flights and accomodation in Evora for two nights or so would only be slightly more expensive than the same price for car hire in the UK, especially at this time of year.
