Abstract
Cosmic rays with energies greater than 10 to the 20th power electron volts have been observed. However, their origin is still a mystery. The Telescope Array (TA) experiment in the Northern Hemisphere and the Pierre Auger Observatory (Auger) in the Southern Hemisphere have been conducting observations to reveal the origin of ultra-high-energy cosmic rays (UHECRs). Here the recent results on energy spectrum, composition, and anisotropy of arrival directions of UHECRs will be presented. Prospects for future UHECR observations will also be discussed.