You can read some about Castle Frankenstein HERE
But as to "Dr. Frankenstein":
Johann Konrad Dippel, 1673-1734, German theologian and alchemist.
Little is known certainly of Dippel, whose life is shrouded in mystery and legend. His interest in alchemy led him to search for the elixir vitae and the philosopher's stone, and he is said to have been interested in creating artificial life. He was also alleged to practice grave-robbing. Dippel's Oil, a concoction of bones, blood, and other bodily fluids distilled in iron tubes and other alchemical equipment, was intended as the elixir vitae, but served only as a stimulant. Dippel offered his next formula, which he claimed was the true elixir of life, to the Landgrave of Hesse in exchange for Castle Frankenstein. It is said that Dippel signed his name "Frankenstein" after his place of residence.
The connection between Dippel and the Castle of Frankenstein on the Rhine near Darmstadt has led some critics to suggest Dippel as the original of Mary Shelley's Victor Frankenstein. But the paucity of material about his actual life leaves much room for doubt, and many of the traits attributed to him may postdate Mary Shelley's novel. There is also considerable doubt about whether Mary Shelley could have known about Dippel's life.
The question is, what ties does the castle Frankenstein have with Mary Shelly's novel? In 1814, Mary Shelley and her lover and later husband, Percy Shelley were traveling through Germany. It is believed that the Shelleys visited the Burgstasse region during a river boat trip. In the early 1800s, the castle was visible from the Rhine and possibly provoked an excursion into the surrounding villages. Why are some literary scholars convinced? There is a connection between Victor Frankenstein and Konrad Dipple, a resident and alchemist who was born on August 10th, 1673 in the Frankenstein castle.
Konrad Dipple was a rogue student at the University of Giessen. He was a scholar of radical thought and left the University after finishing his thesis entitled, De Nihilo (On Nothing), which implied that he had learned very little, or nothing from his instructors. It was then that began to travel the countryside, lecturing on subjects as divinity and astrology. Later he relocated at the castle Frankenstein, the place where he felt his family roots. Even though Dipple had no common blood with the family of Frankenstein, he considered himself a member of the Frankenstein legacy.
He became known as "Dipple the Alchemist" as was believed to have been trying to create a chemical that would prolong one's life. Rumors circulated stating that he was collecting body parts to assist in the making of this formula. Dipple claimed that his formula was to allow him to live to the age of 135 but it is believed that he died by drinking his own potion. On the morning of April 24th, 1734, Dipple's body was found by one of his friends. He became another legend in the history of Frankenstein.
Could Mary Shelley been told of Konrad Dipple during her presumed visit of the castle? There are connections in her story that affirm this thought. The character of Victor Frankenstein is similar to the Alchemist Dipple. Both had a passion for life. Both left their university studies to delve into a dangerous science. Both died tragically from the makings of their obsession-the obsession of harnessing life and the futile attempt to reject the manifestation of death.