Saturday was busy at the country’s biggest airport: up to 110,000 passengers flew off on holidays from Zurich on Saturday, with queuing inevitable. The most popular summer destinations are Spain – including Madrid, Alicante and Barcelona – and Portugal, including Porto, said Swiss International Air Lines (Swiss). Stockholm is also very popular, with many presumably hoping for cooler temperatures. For long-haul flights, destinations in Asia are popular: these include Bangkok, Singapore and…