|Created by||Judy Katschke
|Written by||R.L. Stine (head writer)|
|Country of origin||United States|
|No. of seasons||6|
|No. of episodes||134|
|Executive producer(s)||Kit Laybourne|
Michael Holman (1989-1991)
|Running time||25 minutes|
|Original channel||Nick Jr.|
|Original run||September 4, 1989– June 30, 1995|
R.L. Stine co-created the show with Judy Katschke and was the head writer.
The puppet design and construction for the characters were done at 3/Design Studio where the puppets were built by James Kroupa, John Orberg, Kip Rathke, and Matt Stoddart
The show follows various puppet characters (in the style of Sesame Street), including Eureeka, a sorceress-in-training. She and her friends live in a wind-up castle music box owned by a friendly Giant. Other characters include Magellan the Dragon, Bogge and Quagmire, Batly the Bat, and Mr. Knack. There are also various appearing creatures such as mice, singing fish statues called the Fishtones, Magellan's pets Cooey and the Slurms, and Batly's pet spider Webster.
- Eureeka (performed by Cheryl Blaylock) - The title character. Eureeka is a friendly sorceress-in-training. Her spells are not successful most of the time, but she keeps trying until she gets it right.
- Magellan (performed by Noel MacNeal) - A large green dragon whose tail has a mind of its own. He's the youngest inhabitant in the castle and as such doesn't always understand new concepts. He tends to make great big sneezes that can shake the whole castle whenever he gets upset.
- Batly (performed by James Kroupa) - An egotistical clumsy blue bat who wears glasses due to being near-sighted. Despite being different in every way, he and Magellan are good friends. His flying usually ends with a crash landing prompting him to say "I meant to do that". He spends most of his time in the belfry and has a large bug collection.
- Bogge and Quagmire (performed by Brian Muehl and Pam Arciero) - The Moat Twins are siblings who spend most of their time swimming in the castle moat, eating peanut butter sandwiches, and playing in the basement. Bogge is orange and has two arms while Quagmire is pink and has four arms. They tend to argue with each other, but work together when it comes to causing trouble. Bogge and Quagmire constantly try to steal Magellan's peanut butter sandwiches, but never succeed.
- Mr. Knack (performed by Brian Muehl in an Italian accent) - The castle's handyman and tinkerer. He uses many unconventional methods for fixing things around the castle. He also loves to barter when he sells some of his inventions that he has made from his pushcart. Mr. Knack always gets some postcards which he reads to the viewers.
- Sir Klank (performed by James Kroupa) - An old blue mouse with a long grey beard that resides in a suit of armor.
- Kate (performed by Lynn Hippen) - A pink mouse who frequently reports on what happens in the castle.
- Fishtones - A trio of singing fish in the form of a stone fountain who spray water when they're not singing.
- Giant (performed by James Kroupa) - A full-bodied giant with a long nose who owns the wind-up "castle music box" where the show takes place.
- Pam Arciero – Quagmire, Emma
- Cheryl Blaylock – Eureeka
- Lynn Hippen – Cooey, Kate
- James Kroupa – Batly, Sir Klank, Giant
- Noel MacNeal – Magellan, Webster
- Brian Muehl – Bogge, Mr. Knack
- Eureeka's Castle: Sing Along With Eureeka [VHS] (1995)
- Eureeka's Castle: Christmas at Eureeka's Castle [VHS] (1995)
- Eureeka's Castle: Wide Awake at Eureeka's Castle [VHS] (1996)
- Eureeka's Castle at the Internet Movie Database
- Eureeka's Castle at TV.com
- Entertainment Weekly article