• A visit at the open market on Wednesday or Saturday and then a lunch at the Mercado da Vila
  https://www.cascais.pt/sub-area/feiras-e-mercados

• Afternoon tea at the Albatroz Hotel
  https://www.thealbatrozcollection.com/albatrozhotel/cascais-afternoon-tea

• A walk on the Paredão and a moment at the beach Praia do Tamariz
  https://www.cascais.pt/galeria-de-imagens/paredao

• Seafood at Surpresa (Estoril)
  https://goo.gl/maps/nTTByj4ibdVvaiAy7

• Go by train from Cascais to Lisbon and enjoy the seaview

• And for a second day:
  Casa da Guia – Cascais: https://casadaguiacascais.pt
  Restaurante Furnas do Guincho: https://www.furnasdoguincho.pt/

• Other ideas: https://www.timeout.com/cascais

In Lisbon

• A visit to the Oceanário de Lisboa
  https://www.oceanario.pt/

• A walk in the Jardim da Estrela
  https://www.jf-estrela.pt/comunidade/locais-a-visitar/1-jardim-da-estrela

In Sintra

• A visit to the Quinta da Regaleira
  https://www.regaleira.pt

Further away

• Praia da Saude (Costa da Caparica)