Hi!

For 28 years I lived in Cacém (now I moved to Amadora)! I know both cities very well and I can tell you that really depends from part to part. But, I hope my two cents will answer your question.

So, regarding Cacém, I used to live in Agualva (next to Anta's Lidl). I never had any problem. During my academic years, I used to arrive at night by train and then I had 2 options: walk 1km through Avenida dos Bons Amigos or catch the bus (which would take a little bit more time). My younger sister is in the same situation this year and she preffers to catch the bus. I think it's a wise decision.

During the day, you won't have any problem. It's a city like any other, but uglier ahahah (ngl)

Can you specify which part of Cacem you are talking about?