Questions & Answers about Lisboa é mais interessante do que Londres.
Why do we use two words, do que, to mean "than"?
In Portuguese comparatives, "than" is usually translated as do que. You might sometimes hear people drop the do and just say mais interessante que, which is also grammatically correct, but using the full do que is very common and natural in Portugal.
Why is there no "the" before the cities, like a Lisboa?
Most cities in Portuguese do not use a definite article (o or a) before them. There are a few famous exceptions, like o Porto, but for both Lisbon and London, you just use the name by itself.
Why does this sentence use é instead of está for "is"?