oh lisbon is so beautifull and romantic. if you would like to see something different go to Chapito-it is a circus school and restaurant (my favourite place) under the Castelo de Sao Jorge, go explore Alfama (be ware of the pickpockets in this narrow streets-don’t bring the most expensive camera:)it is a beautifull part of Lisboa, go sit on the Miradours the terras bar with a view, you have a lot of them to visit and drink galao- its coffee with a lot of milk.One beautifull terras is under the Castelo de Sao Jorge, and Graca is also one of my favourites. Traditional music is Fado- there are restaurants with fado singers also.
You can visit Sintra by train, and also Cabo da Roca-the most western point of Europe-where the land finish and the sea begin-it is spectacular!And then go to the beaches nearby.
You can also visit Belem to see the Torre de Belem and Mosteiro de Jeronimos and taste their famous pasteis de Belem-but don’t waste time waiting in line, you can try it in some different caffe as well. I was also fascinated by Aquarium in Parque das Nacoes and everone should see Lisbon nightlife in Bairro Alto. In Chiado you have great shops, for souvenirs i recomend a shop A vida portuguesa (portuguese life) on rua Anchieta 11, Chiado…

There is a lot more but I was in Lisbon for a half of year, maybe some local people know better and it also depends what kind of things you like to do-if you like surfing then go to Caparica beach on the other side of the bridge.

I can say that the whole time I was in Lisbon I was wishing my boyfriend was with me…I think you will have a gret time-but don´t get all crazy to see this and to visit that…Lisboa has this special feeling and this sunlight…just go there and enjoy Lisboa, I know you will!!!

I wish you the best honeymoon ever!

Nincika

Hi!
I’d advise taking a taxi or a tramway to the castle hill, visiting the castle for a view, doing a stroll around Alfama, down the hill to the Rossio (you can visit the Sé on your way down) – go down rua Augusta to see the Praça do Comércio, maybe have lunch at the Martinho da Arcada, go through Rua do Ouro, take the elevator up in the Rua do Ouro to the Chiado. Stroll the Chiado, there’s some nice coffee shops (Brasileira, Benard), the Chiado Museum, take a look at Bairro Alto, visit Miradouro de São Pedro de Alcântara (view). From Bairro Alto up to Principe Real there are some nice old bookshops and antiques shops. I’d also advise visiting Belém and the Museum of Ancient Art, depending on your interests/time left, etc.. The Musem of Ancient Art is kind of a history of Portugal thing since it gathers lots of pieces from our “traveling times”. It’s a small but really lovely museum. Belém is more touristic, it’s a bit the image of Lisbon with the monastery and the big impressive monuments. It’s also a nice place to have lunch, or have the pastéis de Belém (Lisbon’s best-known pastry).
To eat I enjoy: LA cafe (there are 3 – 2 in Avenida da Liberdade and one in Entrecampos), Versailles for lunch (in Avenida da República), small restaurants at Bairro Alto such as Papaçorda or Primavera, Bica do Sapato in the riverside. The restaurant at the castle is also quite good. On the less trendy side there is Hard Rock Cafe at Avenida da Liberdade.
I have lived in the city center for quite a while but am now living near Caparica, by the beach, in a place called Aroeira.
The beaches here are very nice but also on the western coast of Lisbon, for example in Guincho, Praia da Cresmina…
Have fun in your trip.

Hi
I will try to restrict myself by not putting things already covered in other answers. It’s a while since I was there but I think tram 28 still runs and that’s a gem of a route down streets barely wider than the tram.
The Calouste Gulbenkian Museum is small but very, very good.
The Botanical garden and the hothouses at the top left of the Eduardo park are worth seeing.
There is a great viewpoint at the top of the Elevador Gloria and you should certainly try the very different Santa Justa elevador.
There was a bus ticket valid until early the following day {not 24 hours!) which is valid on elevadors and very good value.

2 trips out:
Train to Sintra, hop on hop off bus ticket to National Museum, Castelo dos Mouros and Pena Palace, bus to Cascais, train back to Lisbon

Ferry to Montijo, bus to Setubal, bus to Sesimbra, local bus (return) to fishing port, bus to Cacilhas, Ferry back to Lisboa.

Hi just wanted to add one thing to the great placed mentioned b4. What ever you do don’t forget to visit Cristo Rei in Pragal, and do go enjoy an evening at Gare Maritima de Alcantara.Just pick a place to dine and then who knows go salsa or something.
Enjoy your time there.