There's lots to see across the islands, from archaeological remains to idyllic villages or interesting museums. On Aegina, the 5th century BC temple of Aphaia, surrounded by olive trees overlooking the sea, is a highlight. Paleohora village is fascinating too. Once the capital, today it's a ghost-town with 365 churches, some boasting beautiful frescos.
Hydra town with its red-tiled houses and narrow alleyways is a wonderful place to wander through when enjoying your holiday on the Saronic Islands. In Poros town, the Archaeological Museum is worth a visit, as is the public library and the church of Agios Georgios, known for its amazing frescoes. Spetses town is architecturally beautiful and there are several good museums. Look out for Anargyros Mansion, one of the finest examples of neo-classical architecture.
The islands all have their own character and charm, so a day trip to explore a neighbouring isle is interesting and easily done. But you don't need to leave the island you're staying on - they all have plenty to do and see.
Spetses' pine forests are perfect for a day's walking or cycling. From Aegina you can visit the tiny islet of Moni, deserted apart from the wild goats that live there. Renting a 4x4 in Poros and exploring its undiscovered charms is fun – many churches and monasteries are dotted amidst lush vegetation. Boat excursions with snorkelling and lunch included are popular too from all the islands.