From San Sebastián · 43.32° N · 1.98° W
Getaways from San Sebastián for 15 August, in the middle of Semana Grande: Gavarnie in its best month, northern Palencia, Burgos and Silos, the Matarraña and the Arcachon bay.
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August is one of Gavarnie's best months: the path to the waterfall, free of snow, and the cirque restaurant and hotels open. 15 August is also a holiday in France, and on the path there are more people and horses: start walking before nine and continue to Troumouse in the afternoon.
Aguilar de Campoo is at almost 900 metres and in August the nights are cool, when the coast sleeps in damp heat. The Convento de Mave serves lunches in summer: order the roast lamb when you book. The Sunday European bison are seen with a guide and booking.
In August the Atapuerca sites continue with guided visits, and Burgos empties of city people, who go off to the village. Book the visit by phone, and the wood-fired lamb. If the 15th falls on a Monday, remember that many Burgos museums close on Mondays.
Silos in August is a stone village with cool nights and vespers sung every afternoon in the monastery. Do La Yecla or the juniper-wood route in the morning: at midday the sun beats down on the moor. Casa Galín is booked beforehand.

In summer the Sunday plan swaps the Ports for the Pena reservoir, with swimming, and the Parrizal de Beceite is walked on walkways beside the river. The Parrizal ticket sells out in August: buy it as soon as you have the date.

August is one of Rioja Alavesa's quiet months: the vineyard is laden with green grapes and the harvest is weeks away. If the 15th falls midweek, it fits with the opening days of Héctor Oribe and Baigorri. In August some wineries close for holidays: confirm when you book.

For those who want the sea away from home in the busiest week: in July and August there are traffic jams towards Cap Ferret and 15 August is a holiday in France. Climb the Pilat dune first thing or at dusk, and eat the oysters in the hut at midday, when the beach fills.
Questions
It is held each year in the week of 15 August, with fireworks over the bay every night. The exact dates are published by the council.
Yes, because it is high season and 15 August is a holiday in France. Start walking before nine and leave the Troumouse and Estaubé cirques for the afternoon.
On the plateau: Aguilar de Campoo and Silos, at almost 900 and nearly 1,000 metres, have cool nights even in high summer.
Most do, although some small ones close for holidays. Confirm it when you book the tasting.
Geocaliahttps://www.geocalia.com/en/spain/basque-country/san-sebastian/getaways/august-long-weekend