Donostia is the basque name of San Sebastian. It is a beautiful city at the atlantic ocean with two beaches, one is surfers paradise and one for swimmers. A little island in the sea. A Jesus on a rock. An old part with lot of shops and pubs. It is very compact, so you could use the bus but you can also walk from point A to point B.
Insider Tip:Walk to the Jesus to see all the city from above. Only five minutes from part of Gros you can walk at the coast on the camino de Sandiago. Go to Erreneria by bus or train and you can cicle or walk to mountains from where you can see San Sebastian, Irun, Hendaye, Biarizz and much more.
In the night the Tas Tas Bar is good to meet people from all over the world.