Highball Signal is a historic railroad signal located in Delmar, Delaware. It is a white ball mounted on a pole and located next to the railroad tracks. If the ball was at the top of the pole, it indicated permission for a train to proceed at full speed. The term "highball" came to be synonymous with a clear right-of-way and for trains to proceed at full speed. It was originally in service at New Castle, Delaware and then at Hurlock, Maryland. The Highball Signal was moved to its permanent location in Delmar, Delaware for display during the town's centennial in 1959. It is no longer used to direct railroad traffic, but is maintained as a public exhibition in a park near the railroad.