Shore Temple, Mahabalipuram, India

Postcard IN-177804 from India shows the Shore Temple, built with blocks of granite in 700–728 CE, overlooking the shore of the Bay of Bengal at Mahabalipuram in India. It is one of the oldest structural stone temples of South India. Mahabalipuram was once a busy port during the reign of Narasimhavarman II of the Pallava dynasty. 

As one of the Group of Monuments at Mahabalipuram, the Shore Temple was recognized as part of a UNESCO World Heritage Site in 1984.

Orton Hall at OSU, Ohio

Postcard US-3620809 to China shows Orton Hall, one of the oldest remaining buildings on Ohio State University campus. Opened in 1893, it was named after Dr Edward Orton, Sr. who served as OSU's first president, Professor of Geology from 1873 to 1899, and Ohio's State Geologist from 1882 until his death in 1899.

According to Wikipedia, the Hall is built of forty different Ohio building stones. In the outside walls, these stones are laid in stratigraphic order according to their relative positions in Ohio's bedrock. The capitals of the numbered columns in the entrance hall feature carvings of fossils, such as trilobites, as well as other objects such as the races of Man. The bell tower was dedicated in 1915 and contains 25,000 pounds of bells that can be heard regularly tolling across campus in the key of E-flat. Encircling the top of the tower are 24 columns with gargoyle-like figures which are restorations of fossil animals. Orton Hall was placed into the National Register of Historic Places on July 16, 1970, along with University Hall and Hayes Hall. It presently hosts the School of Earth Science, laboratories of Paleontology, Historical Geology and Sedimentology, the Orton Geological Museum, and the Orton Geological Library.

Kõpu Lighthouse, Estonia

Postcard EE-185518 from Estonia shows the Kõpu Lighthouse on the island of Hiiumaa in Estonia. One of the best known landmarks in the country, it is one of the oldest lighthouses in the world and has been in continuous use since 1531.

The 36-meter or 118-foot tall lighthouse, built on top of the highest hillock Tower Hill, marks the Hiiu sandbank. At the altitude of 102 meters or 337 feet above the sea level, its light can be seen from as far as 26 nautical miles, or 48 kilometers or 30 miles away. It is the highest coastal light on the Baltic Sea.

What special about this lighthouse was its solid base when originally built. Keepers had to use external wooden stairs to reach the top of the lighthouse. A staircase was embedded into the tower during reconstruction in the 1800s.

The postcard has a 2014 the Year of the Horse stamp issued by Estonia Post.

Lake Baikal, Russia

Lake Baikal, Russia

The postcard RU-1836095 received yesterday shows Lake Baikal, a rift lake, in Siberia, Russia. Lake Baikal is the most voluminous freshwater lake in the world. It is also the deepest (1,642 m or 5,387 ft); the clearest;  and the oldest (25 million years) of all lakes.

Lake Baikal area is home to more than 1,700 species of plants and animals, with 2/3 of those being unique to the region. It was declared as a UNESCO World Heritage Site in 1996.