Swallow Grotto

Postcard TW-1240742 from Taiwan shows Swallow Grotto (Yantzkou 燕子口), a section of the Central Cross-Island Highway 500 meters from the Jinheng Park (靳珩公園) near Hualien, where the Liwu River twists and turns in the deep and narrow gorges. It is part of the Taroko National Park in Taiwan.

Several tunnels had to be built for the highway to pass through cliffs. Visitors could walk through the tunnels, enjoy the sight of streams below, and numerous small swallow grottos on the marble cliffs. However, swallows have moved away due to heavy human impacts.

Mount Olympus

On this Earth Day came postcard GR-38421 showing Mount Olympus, the highest mountain in Greece with 52 peaks, deep gorges, and exceptional biodiversity. According to Wikepedia, its highest peak Mytikas, meaning "nose", rises to 2,917 meters or 9,570 feet and is one of the highest peaks in Europe in terms of topographic prominence. Olympus was notable in Ancient Greek Mythology as the home of the Twelve Olympians. Mount Olympus is also noted for its very rich flora with several special species. It has been the first National Park of Greece since 1938, and a World's Biosphere Reserve.