Two letters home believed to be the world's oldest are currently displayed at the Yunmeng Xiangshan Museum in Xiaogan, Hubei Province.
The two letters, inscribed on wooden tablets, were written some 2,200 years ago by brothers Heifu and Jing to their brother in "Zhong," their home hometown. The brothers were soldiers in the Qin army, located then in today's Huaiyang County, Henan Province.
Acquaintances of the brothers delivered the letters home as personal letters were not allowed to be conveyed via official mail until the Song Dynasty.
The inscriptions were made toward the end of the Warring States period and were discovered in Dec. 1975 in the west suburb of Yunmeng County in Hubei Province.
The letters have been kept in good condition, with ink handwriting still visible and recognizable.
The artifacts provide an insight into the social and economic development as well as the letter-writing conventions during the period they were made, according to China Daily.
One of the differences noted by scholars was the way the date was written at the beginning of the letter rather than the end, as is currently practiced.
Researchers also found that some words used in the letters are still part of today's Chinese vocabulary.