My friend, the historian G. Rex Smith, has recently translated into English a marvelous travel diary by the French military official and traveller Pierre Loti (1850-1923). It is also available on Amazon as a Kindle Book. This day-by-day diary details Loti’s trip along the caravan trail of 1900 from the coast at Bushire to Shiraz and his ultimate goal of Isfahan in order to visit the area during the season of roses. One might expect such an account to be dry, but Loti comments on what he saw, including the people, along the way and one gets a first-hand sense of what it was like to travel a treacherous route that was at times over pure desert and at other times up or down seemingly impenetrable mountain heights. There is also a brief account of his stop at Muscat on the way to Persia. Smith, with the aid of his son, has done an admirable job in reflecting the flavor of the original French and includes 24 photographs taken by Loti. This is a book well worth reading, whether you are interested in Persia at the time or not.
The original French version is available as a pdf here. Archive.org has quite a few of his works.
For information about Loti online, check out https://biography.yourdictionary.com/pierre-loti and https://museeprotestant.org/en/notice/pierre-loti-1850-1923-2/.