The Alpine range in Graubünden divides the northern European climate from the Mediterranean weather of the south. In the inner Alpine region the precipitation is low, offering holiday-makers plenty of sunshine. Altitude plays a key role in terms of temperature. A general rule of thumb is that the temperature drops between 0.5 – 1.0 °C for every 100 metres of altitude. The best time for winter holidays is between the end of November and mid-April and for summer holidays the best time is between mid-June and mid October.