TT Assen is a renowned motorcycle racing event held annually at the TT Circuit Assen in the Netherlands. Established in 1925, it is part of the MotoGP calendar and attracts thousands of fans each year. The circuit is known for its challenging layout and rich history in motorsport. The event features various classes of motorcycle racing, including the premier MotoGP class, as well as Moto2 and Moto3. The TT Assen is unique for being the only race that has been held every year since its inception, making it a significant part of motorcycle racing heritage.