I have never really thought about Lisbon but i was really surprised in a positive way when i got there. It is a lovely town with a lot off architect, old houses mixed with new in a  way that makes the town very unique and charming.
To me it reminded me a lot off san fransisco, the yellow term going threw town, the so steep hills, the closeness to the sea and also when you are by the sea and look over the water you see the 25 april bridge with a little feel off the golden gate bridge adding to the san fransisco feel.
The 25 off april bridge is definatly something worth seeing, as you get down to the terrero dopaco or park de comercio you look out on the ocean and it is a sight for sore eyes. when i was there it was starting to get rather late in the afternoon, there was a band playing music right by the water and you could seat down by the water and just listen to the ocean and the nice classic music enjoying the lovely worm weather.
The square is surrounded by restaurants and not far from there you have several main streets that all have many many restaurants with traditional and international food.
Another place that is a must see is the Sao Jorge Castle that is up on the highest hill in Lisbon. You walk up or take the trem part off the way up this very steep hill until you get to the top and see a 400 year old castle that overlooks lisbon and the tagus river.
One place that i recommend is the santa justa lift. In the middle off the shopping street you will find a very odd looking building that will catch your eyes making you wonder what it is.  You can go up on it by lift. And from the very top you have yet another lovely sight over town and this time you have brio alto at your back.
I really only had a weekend there is Lisbon so i didnt get to see much more but from what i hear the night life in the barrio alto is espouse to be something worth a try.
What i did though was to leave the city and go to a smaller town close to the capital, Ericeira. I went there for a week long surf camp.
Ericeira is one off Europes bigger places for surfing, you will find many many surfing camps and renting places all over this little town. The water is real cold and i hardly saw anyone swim more then a few kids and for surfing you have to have the wetsuit but you will find many places for surfing for any level surfer.
The town it self is a real pearl. beautifully located on the high mountains surrounded by the ocean. There are many places for eating, both local places and international food. while there one night we went out on town and it was the coolest thing, the entire town was out on the streets partying, there was no real club, but it was alcohol being served on the streets and live music to dance to right on one off the small streets off this town.
The town has not much more for seeing and doing except surfing. But there is a famous tattoo studio in town if you want to get a tattoo before returning home.

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