Earlier this month, I visited Lisbon for the first time. It is not as warm as I thought, and it can be quite windy and rainy in March. The food we tried, in general, was all relatively cheaper and tasted better than Isle of Man. Just bear in mind, it takes ages for the food to be put on the table.
1. Downtown Lisbon
I like their massive use of pastel colors on their buildings but you can also see a lot of wear and tear. Another distinct feature in their architecture is they love using tiles in decoration.
2. Some vibrant street art
3. Museum of marina
The majority of the exhibits belong to the Age of Discovery. 
4. Portuguese food
I bought the famous pastry- pastel de nata from several places, and personally speaking, the pastelaria near Castello de Sao Jorge is the best. Its pastries are served warm and not too sweet.
To be honest, Portuguese local food is very cheap and most of them are quite yummy. We went to a fancy restaurant called "Infame", not only the food is well presented, its espresso is just divine.
I highly recommend a very unique local restaurant- O Pescador, not only for its high-quality food, but also for this portrait wall.
I am going to follow up on this post with more from my recent trip to Portugal and more food adventures in the Algarve.