Why don't you try a roller coaster called " Thunder Dolphin"? It's sooooooooooo scary ( for me...... maybe....), but good for fun!!
Open until 20:00, everyday ( it might close due to the weather condition. )
* How to get to Korakuen from the hotel ( it will takes about 30minutes to get there )
Inaricho Station. ( 3minutes walk from us )
↓ Metro ( Ginza line)
↓ JR ( Chuo line )
↓ JR ( Sobu line )