There are more than 7,000 sirens across the country – and once a year, they’re checked.
There are two basic types of alert – the General Alert, which could mean anything, from rocket attack, earthquake or even a tsumani – yes, they’re possible on lakes.
There’s also another alarm specifically for those who live near dams – for obvious reasons.
The advice is, if you hear an alarm, then switch on the radio, or go to the government information portal ch.ch.
But if you’ve downloaded the Alertswiss app on your phone, that will also provide the information needed.
But if you hear it today between 1.30 and 2pm – you don’t need to do anything.
Switzerland relies too heavily on an American NGO to detect child sexual abuse online, raising questions about the country's ability to protect children on its own.
Summer has arrived, with temperatures climbing past 30 over the long weekend. Basel reached 31 and Sion hit 32.4, but MeteoSwiss, says this does not yet count as an official heatwave.