Police fired tear gas at demonstrators who carried flags and banners against Mrs Merkel’s visit to Greece. The German Chancellor has travelled to Athens for talks with Greece’s Prime Minister Alexis Tsipras.
Mr Tsipras said the visit marked “the end of a difficult cycle between our two countries”.
Germany is seen as one of the main enforcers of rigid austerity measures in Greece after the country required a series of bailouts from the EU.
Greece has faced tax rises and harsh pension and salary cuts in return for three massive loans to bail the government out of its severe debt.
Speaking ahead of the visit, Mrs Merkel told Greek newspaper Kathimerini: “I realise that the last few years have been very difficult for many people in Greece.”
But she said that the country has made “great progress”, adding: “Greece and Germany have close ties both via a plethora of bilateral relations and as partners in the EU and NATO.”
Mrs Merkel went on to say that she was looking forward to “good talks and interesting meetings” during her visit.
Speaking on Monday, Mr Tsipras told TV channel Open Beyond that Mrs Merkel had wanted to visit Greece for “some time”.
He said: “She has wanted to come for some time because she considers it also her own success that while Greece was on the verge of bankruptcy in 2015, it has managed to recover and of course remain in the central core of the EU.”
Mrs Merkel is also set to meet Greek President Prokopis Pavlopoulos and the conservative opposition leader, Kyriakos Mitsotakis tomorrow on the second day of her visit.