Portugal Rental Car

You have not conducted a search yet, have you?

OK. You just have to type "Lisbon Port" (or the address of the Port if you have) into the search engine and choose the Port from the drop down menu. Also, this may help:-

During the booking process once you have entered your search criteria, you will see car photos (results). At the top right hand side is a drop down filter, choose "SORT BY DISTANCE”. This will shuffle the available cars based upon nearest, with a small map. The specified distance above the map is the distance from the inserted desired location to the location of the nearest supplier. Click on the little map to expand and the exact address/location will be shown.

Also because you are trying to return it on a sunday the website probably wont have shown you cars. I can see available cars.