A double helping of volcanoes. Both the postcard and the stamp show volcanoes in the Kamchatka region of Russia. The postcard shows the Gorely volcano with an acid lake, the Blue Lake. The stamp shows the Karymsky volcano which has been erupting non-stop ever since 2013 and fairly continuously since 1996.
The whole area of the Kamchatka peninsula was added to UNESCO's World Heritage list in 1996 but I'm afraid I hadn't heard of it until this card arrived last week. There are about 300 volcanoes and of these, 29 are still active.
This is a post for Sunday Stamps, now hosted by Violet Sky at "See it on a Postcard!"