PORTUGAL is part of the Schengen area. Schengen Area Member States will generally provide Uniform Schengen Visa valid for all Schengen area (unless otherwise noted on the visa sticker).
The countries one can travel to, once he/she holds a Uniform Schengen Visa include:
The Schengen Area Member States: AUSTRIA, BELGIUM, CZECH REPUBLIC, DENMARK, ESTONIA, FINLAND, FRANCE, GERMANY, GREECE, HUNGARY, ICELAND, ITALY, LATVIA, LITHUANIA, LUXEMBOURG, MALTA, NETHERLANDS, NORWAY, POLAND, PORTUGAL, SLOVAKIA, SLOVENIA, SPAIN, SWEDEN, SWITZERLAND, LIECHTENSTEIN.
European microstates which abolished the border control and embraced the free movement among the Schengen Zone Countries where the Schengen visa rules can therefore be regarded to apply de facto: SAN MARINO, MONACO and THE VATICAN
BULGARIA, CROATIA, CYPRUS and ROMANIA can also be visited with multiple entry Schengen visa even though not part of the Schengen area. Please check the details directly on the country information window.