BEST food in Old Town - amazing tomatoes, shishito peppers and steak. They only make 2 spanish omelettes each day and people go nuts (line up down the street) to get a slice :)
Can do a scheduled tour or DIY!
Take the funicular up to the top of the mountain which overlooks all of San Sebastian with breathtaking views of the water! There's also an amusement park up there :)
STUNNING views and beautiful ambiance
Good for hiking!