In Greece, the Presidential Guard is a unit of the Greek Army guarding the Tomb of the Unknown Soldier and the Presidential Palace. Its members, known as Evzones, must be taller than 1.85m and are trained hard as their duty includes standing completely still for more than an hour 4 times a day. They are famous for their military discipline, the ability to stand motionless without even blinking, their stylish walking and the uniform which derives from traditional Greek dress. A tri-service guard of honour composed of servicmen from the Hellenic Army, the Hellenic Navy, and the Hellenic Air Force is maintained as part of the Ministry of National Defence.