Parque das Nações ("Nations' Park") is also known as just "Expo" by locals. This is Lisbon's most recently developed neighborhood, namely launched in 1998, full of modern buildings and attractions, including the city's Oceanarium, the Oriente multi-modal station, Vasco da Gama shopping mall and a cable car system overlooking the Tagus river.
This place is the result of an unprecedented re-urbanization project planned for the 1998 Lisbon World Exposition ("Expo 98"), commemorating five centuries of Portuguese discoveries with the slogan "The Oceans, a Heritage for the Future". It is home to several nice restaurants and to the headquarters of some of the largest international companies.
Exploring Parque das Nações by foot is a nice way to get to know the whole area.