Lisbon - a montainous city worth climbing :)
A very loud, montainous, crowdy city. Especially in the summer. But it is totally worth your visit - it has some beautiful views from viewpoint, a big nice river, it is close to the ocean and has a lot of nice museum etc. to visit. Don't miss the castle of St. George, Cathedral or St. Roque Church, they are really good places to visit! And the archeological museum which consists of ruins of enormous church - totally wonderful! Prepare for a long walks - and wonderful food and vinho verde :)
Insider Tip:Most museums are closed on Monday - and some are cheaper or free on Sunday! Beware of the pickpockets. The city in the summer is very crowdy and they have it easy to take advantage of the tourists. Look for "mini-preco" shops to buy simple things like water or juice, it is cheaper than in small shops. Buy your tram ticket at the metro stations, it is much cheaper! And when you're waiting on the tram stop, remember to wave at your tram, otherwise it goes by. Mercado is a cool place to eat a dinner.