The city is only about 10 miles from the French border but is thoroughly Spanish – and its dramatic coastline gives it a glamour that visibly rubs off on its population.
The closest airport with flights from Britain is Biarritz, across the border in France. You can fly from Gatwick with easyJet (0843 104 5000;easyjet.com) or from Stansted and Manchester with Ryanair (0871 246 0000; ryanair.com).
Pesa buses link the airport to San Sebastian's bus station (1) in 45 minutes (fare €6.60) but there is only one daily departure, at 3.30pm, returning from San Sebastian at 2.30pm (00 34 902 101 210; pesa.net).
Bilbao, 60 miles to the west, is served from Stansted or Manchester by easyJet and from Heathrow by Vueling (0906 754 7541; vueling.com).
From Bilbao airport, Pesa operates hourly buses from 7.45am to 22.45pm to the bus station (1). The trip takes about an hour and costs €16. Tickets can be bought from the conductor on board the bus, which leaves from outside arrivals.
Alternatively, take a ferry from Portsmouth to Bilbao with Brittany Ferries (0871 244 0744; brittany-ferries.co.uk). When you reach the port at Santurtzi, there's a train to Bilbao's city centre, from where you can hop on a bus or train to reach San Sebastian.
Get your bearings
San Sebastian occupies a bay formed by the mountainous Cantabrian coastline. The Sacred Heart statue on Monte Urgull (2), the bay's eastern headland, towers over the Parte Vieja (Old Town). This district of narrow streets is the main hub, squeezed between the mellow La Concha beach to the west and the mouth of the Urumea river as it flows into the Bay of Biscay.
The main tourist office (3) is situated at 8 Alameda del Boulevard (00 34 943 481 166; sansebastianturismo.com; open daily 10am to 7pm, until 2pm Sunday, and closed weekdays from 1.30-3.30pm. Staff here sell the three-day San Sebastian Card (€8) which gives free access to the buses and discounts at some shops.
The four-star Hotel de Londres (4) at Calle Zubieta 2 (00 34 943 440 770;hlondres.com) is a cream-coloured monolith at the eastern end of La Concha beach. An imperialist take on a boutique hotel, it has doubles from €199, room only.
You'll understand why Pension Bellas Artes (5) is so popular when you meet Leire, the affable owner. It's at Calle de Urbieta 64 (00 34 943 474 905, www.pension-bellasartes.com). Spotless rooms with high-pressure showers start at €118, room only. A good location for breakfast, incidentally, is Avenida XXI (6) at Avenida de la Libertad 21 (00 34 943 426 054; farfalle.es), which is open from 7am daily, except Sunday. The house speciality is grilled croissant with marmalade which, accompanied by a café con leche, costs €3.15.
The Urban House (7) hostel at Plaza Guipúzcoa 2 (00 34 943 428 154;enjoyeu.com) is part of a trio of hostels throbbing with activity. It has dorm beds from €16, or doubles from €35, with breakfast included.
Take a hike ...
Start on Calle Mayor at the Iglesia Santa María (8) behind the Parte Vieja, and admire the church's 18th-century Baroque façade, flanked by two towers. Follow the road north and take a right into Calle 31 de Agosto (the only street not to burn when the French attacked on that date in 1813). Continue to Calle de San Vicente, then go right to the rival church of Iglesia San Vicente (9); step inside to sample the stunning light cast by the stained glass. Continue along Calle de San Vicente then turn right on to Calle de Iñigo until you reach the Plaza de la Constitución (10). Note how the windows have seat numbers from when the square was used as a bullring.
Lunch on the run
Stock up with the region's best tuck from Zapore Jai (11) on San Jerónimo 21 (00 34 943 422 882; zaporejai.com, open 10.30am to 8pm), then stroll over to Alderdi Eder Park (12) to enjoy a picnic overlooking the bay.
Pedestrianised Calle Loiola, running north from Catedral del Buen Pastor (13), is the main shopping thoroughfare. On the left as you stroll north, is the San Martín shopping centre (14), around which many of the boutiques cluster (msanmartin.es). Shops open at 9am and stay busy until as late as 8pm. Most shut for siesta around 2pm and are closed on Sundays.
Take a ride
Stroll over to the harbour, where Motoras de la Isla (15) (00 34 943 000 450; motorasdelaisla.com) can ferry you across to the Isla Santa Clara (16) in the middle of the bay (€3.80 return, every half hour from 10am to 8pm). The rocky island has an outdoor bar, a tiny beach and a jetty for splash-happy swimmers.
Atari Gastroteka (17) at Calle Mayor 18 (00 34 943 440 792; noon to 1am daily) overlooks the same courtyard as the Iglesia Santa María (8). Txakoli, a young white wine typical of the Basque Country, is served extremely cold and poured from a height to force fizz into the liquid. It's deliciously acidic. A glass will set you back €1.50.
Dining with the locals
With pintxos, the idea is to eat one or two of what each bar does best, before moving on. Ask at the bar for crockery and you'll get plates the size of car tyres. Don't feel self-conscious when taking only one.
La Cuchara de San Telmo (18) is at the back of a side street running off Calle 31 de Agosto (00 34 647 787 444; lacucharadesantelmo.com; closed Mon/Tues lunchtime). It's well worth the search – this rustically decorated joint produces the most delicious pintxos in town, such as foie gras with apple compote for €3, or cheese-laced risotto cremoso for €2.90. Order from the chalkboards behind the bar; English menus are available.
If you're more postmodern about your food, pop into Zeruko (19), Calle Pescadería 10 (00 34 943 423 451; barzeruko.com; closed Mon/Sun evenings). Sear your cod fillet (bacalao) to taste on the mini grill (la hoguera), or pick from the Turner Prize-worthy candidates – cava-infused cod with chilli "pearls" or a cannelloni of Pedro Ximénez jelly and mushroom pâté – on the bar.
Sunday morning: go to church
The cavernous Catedral del Buen Pastor (13) has the city's largest parish. Built in neo-Gothic style from sandstone, it runs six services on Sundays in four languages (9am to 6pm); check the boards at the entrance for times. The church is open daily (entry free, 8.30am to 12.30pm and 5-8pm).
A walk in the park
The Museo Chillida-Leku (00 34 943 336 006; eduardo-chillida.com) is an outdoor museum dedicated to the Basque goalkeeper-turned-sculptor Eduardo Chillida. It is 8km out of town at Hernani; take bus 92 from Calle de Okendo (20). It has an attractive park speckled with sculptures and a more formal gallery occupying a fine 16th-century farmhouse on the estate. Open 10.30am to 3pm daily except Tuesdays; entry €8.
Out to brunch
Back on the bay, and sitting right on top of the sand, La Perla's (21) two outdoor terraces (00 34 943 462 484; la-perla.net) are smack-bang in the middle of La Concha beach, perfect for lazy people-watching. It's on the beach side of Paseo de la Concha. Tuck into a plate of Iberian ham (€18.95), fried eggs "broken" over potatoes, garlic and truffle (€15.75) or try the French toast with caramelised vanilla and yoghurt ice cream (€7.50).
After four years of refurbishment, the Museo de San Telmo (22) has reopened in grand style. The new edifice hosts the dynamic temporary exhibitions while the stylishly restored 17th-century building houses the permanent exhibit on all aspects of Basque culture. It's located at Plaza Zuolaga 1 (00 34 943 481 580; santelmomuseoa.com; 10am-8pm daily except Monday; entry is €5, free on Tuesdays).
Icing on the cake
From the ground- level station for the 100-year-old funicular (23), pay €2.80 for the return ride to the top of Monte Igueldo (24), the bay's western headland (monteigueldo.es; every 15 minutes from 10am-9pm, until 10pm on weekends).
It commands the best view of the bay and the dramatically rugged coastline to the west. It's also great fun for children – the summit hosts an amusement park.