If you have a connection from 7:00 to 13:30 (check-in) in Lisbon and have to choose only one place to visit, what would be ?
PS. My flight departs at 16:25 pm
I would go to Parque das Nações if I was you.
This is the site that had the EXPO 98 and has today become a very nice part of the city with lot's of modern architecture and good cafes and restaurants.
And it's located right by the river which makes it pleasant too.
And it's a very short drive from the airport.
Only 5-10 minutes by taxe or you could even take the metro if you feel like sav ing a bit of money.
Hi, instead of going to a single place with 6 hours you can easily take the subway at the airport and head downtown to Rossio or Baixa station. It'll take +/-40 min. There you can walk to the river Tejo down Rua Augusta and reach Terreiro do Paço and Ribeira das Naus. +/- 1h After that you could go back and then take the lift Elevador de Santa Justa visit Chiado +/- 1h and walk up the street up to Miradouro Sao Pedro de Alcantara +/- 30m and enjoy a great view from there. To finish you can take the tram ELEVADOR DA GLÓRIA +/- 15m to go down to Restauradores. From ther you take the subway again to the Lisbon Portela Airport +/- 40 m. Enjoy Lisbon!
Mentioned in this answer:
I would definitely jump on the metro and reach Oriente (as you can see, it is very close to the Airport). If you like Santiago Calatrava's works, you'll love it, you can walk by the Tejo and visit the Oceanário de Lisboa... This is a picture I took in November 2013 ;-) I adore this bridge! Have a great time!