The book "Letters of Alexander von Humboldt to Warnhagen von Ense. From 1827 to 1858. With excerpts from Warnhagen's diaries and letters of Warnhagen and others to Humboldt" contains valuable correspondence between two outstanding personalities of the cultural life of the 19th century. The letters that have been published in this book reveal not only the scientific and cultural interests of Humboldt and Warnhagen, but also their mutual relations, shared interests and thoughts about the events of the time. This book helps to better understand the depth of intelligence and feelings of these outstanding personalities of history.