Germany's wine regions are concentrated in the south-western part of the country, which is parallel in latitude (50°) to Labrador. Her vineyards are located on steep south-facing slopes, in a few valleys and almost always close to a river which tempers the climate. Rivers are acting as a heat reflector, helping to maintain a constant temperature day and night. In autumn the mist and fog that rises from the river offers the grapes protection from early frost.