Cliff Davies may refer to:

• Cliff Davies (musician) (1948–2008), British drummer, songwriter and producer, known for his work with If and Ted Nugent
• Cliff Davies (rugby player) (1919–1967), Welsh international rugby player
• Clifford Davis (music manager) British musician and music manager, one-time manager of Fleetwood Mac

• The hardest logic puzzle ever
• The Hardest Logic Puzzle Ever
• The Hardest Part
• The Hardest Part (Blondie single)
• The Hardest Part (Coldplay single)
• The Hardest Part (Coldplay song)
• The Hardest Part Is the Night
• The hardest part (single)
• The Hardest Way To Make An Easy Living
• The Hardest Way to Make an Easy Living
• The Hardest Word
• The hardest working man in show business
• The Hard goodbye (Sin city yarn)
• The Harding Memorial
• The Hard Lessons
• The Hard Lessons discography
• The Hardly Boys
• The Hardmans' House
• The Hardons
• The Hard-Ons
• The Hard Ons
• The Hard Part
• The Hard Part (Heroes)
• The Hard Ride
• The Hard Ride (film)