Dramatic cliffs line the Estoril coast, a strip which runs from Cascais to Lisbon broken up by orange sandy coves. This is a slice of Portugal largely undisturbed by Brits, instead well-heeled Lisboans cross the water in drones in the summer. The crowds peter out by September, when it’s still just about warm enough to enjoy the beach.
The beaches are great for young children, particularly Praia de Duquesa. Here the sand spills gradually into the sea and the waves are gentle enough for swimming. In the summer there’s an inflatable water slide and playground that will keep kids occupied for hours.
A large red pizza delivery number flashes out from a white ice-cream shop, big enough for the yachts to see and call. Your stack of margaritas will then be whizzed over by speedboat in a matter of minutes.
Yachts and motor boats can be chartered through Water X, which will also arrange regattas should the competitive spirit take you, as well as water transfers from Lisbon Airport to Cascais – a novel way to arrive –, donutting, waterskiing and kite surfing.
Hire a car and drive half an hour to Sintra, a UNESCO World Heritage site. Explore the municipality's museums and palaces, which were once home to the royal family during the hot summer months. Up here, it can be 10 degrees cooler than Cascais or Lisbon. A string of marigold manor houses lead you up the twisting mountain road to a charming cobbled centre, where cafés, boutiques and shops await. Tuk tuks, horse and carriages and an electric train are painless ways to see the sights with children.
A further 10 minutes on from the town is Sintra beach, a wild beauty great for paddling. There’s a local taverna serving basic but delicious fish dishes and candy-coloured beach huts for shade.
Where to stay: We love The Oitavos, a family-friendly hotel in Quinta da Marinha - 10 minutes from Cascais.
Getting there: TAP Portugal flies from London Heathrow to Lisbon; from £118 return.
Travel time: The flight takes 2 hours and 30 minutes, it's then a 30-minute transfer by car to Cascais, or you can get the train, which snakes along the cliffs taking in beautiful coastal views. The Oitavos' concierge will meet you at the train station.