Alonnisos (sometimes spelled as Alonissos) is the least popular among tourists island of the Sporades. Although bigger than Skiathos, it is less inhabited and less visited so this is your place if you are looking for a really quiet holiday.
You can reach Alonnisos by ferry from Volos or Agios Konstantinos. The nearest airport is on Skiathos.
The island is 20 km long and 5 km in its widest part. All villages and settlements on the island are set on the east coast, the west one is rocky and no buildings can be found there. Unlike the other islands of the group, its capital and largest settlement is not called Alonnisos but Patitiri. The former capital of the island was indeed a village called Alonnisos but it was ruined by a severe earthquake in 1965 and most its residents moved to Patitiri. Yet there are some house in the village of Alonnisos and you can visit it for a walk. Besides Patitiri, there are 6-7 other settlements by the sea which are very small but yet they offer rooms and villas to rent.
Most of the beaches on Alonnissos are small, with pebbles or shingle. On the western coast there are some beaches which are also accessible by car.
Alonnisos is part of the National Marine Park of Alonnisos which is home to the endangered species Mediterranean monk seal. The park includes Alonnissos and other 28 islands and islets, located around Alonnisos.