The rare first edition of the English translation. In fact, the very first English edition of any of Kafka’s books. The first edition of The Castle was published in German in 1926 by Kurt Wolff.
About the book (from wikipedia):
The Castle (German: Das Schloss German pronunciation: [das ʃlɔs]; also spelled Das Schloß) is a 1926 novel by Franz Kafka. In it a protagonist known only as K. arrives in a village and struggles to gain access to the mysterious authorities who govern it from a castle. Kafka died before finishing the work, but suggested it would end with K. dying in the village, the castle notifying him on his death bed that his “legal claim to live in the village was not valid, yet, taking certain auxiliary circumstances into account, he was permitted to live and work there”. Dark and at times surreal, The Castle is often understood to be about alienation, unresponsive bureaucracy, the frustration of trying to conduct business with non-transparent, seemingly arbitrary controlling systems, and the futile pursuit of an unobtainable goal.
Kafka began writing the novel on the evening of 27 January 1922, the day he arrived at the mountain resort of Spindlermühle (now in the Czech Republic). A picture taken of him upon his arrival shows him by a horse-drawn sleigh in the snow in a setting reminiscent of The Castle. Hence, the significance that the first few chapters of the handwritten manuscript were written in first person and at some point later changed by Kafka to a third person narrator, ‘K.’