This paper asks how strong the evidence is for a large and growing age cleavage in European politics, using new estimates of the ideological positions of different age groups in 27 European countries across four issue domains from 1981-2016, together with age-period-cohort analysis and an examination of voting patterns by age. The young turn out to be much more socially liberal than the old in most countries, but also more opposed to taxation and government spending. Age divides are generally no larger now than they were thirty years ago, are explained primarily by cohort replacement effects, and are likely to fall in the near future. Nonetheless, age divides in voting are large and in some places actually increasing. A likely explanation is that, although age-based ideological differences are not new, parties have increasingly emerged and polarised along the dimensions where the young and old have long differed from each other.