Feira da Ladra
The so-called "thieves" market (it used to be said that stolen items invariably ended up here) is now the most famous flea market in Portugal. You'll need a few hours to browse all the stalls selling everything from vintage clothes to antique furnishings, with plenty of colorful treasures in between. The market attracts serious collectors as well as casual browsers, so arrive early for the best deals. It officially runs from 9 am to 6 pm, but vendors often begin packing up by around 2 pm on Tuesday, and a little later into the afternoon on Saturday.