Grandpa has reached sixty, but he's still hale and hearty.
Tips
culture
花甲 refers to the 六十甲子 - the sixty-year cycle formed by pairing the ten Heavenly Stems (天干) with the twelve Earthly Branches (地支). One full cycle is sixty years, so 花甲之年 means age 60. Related milestones: 而立 30, 不惑 40, 知天命 50, 花甲 60, 古稀 70.
register
Formal and respectful. Use for elders or in writing; colloquially people just say 六十岁 or 六十多岁.