Users often revisit pages while browsing the Web, yet little is known on the character of these revisits. In this paper we present an analysis of various revisit activities, based on results from a long-term click-through study. We separate backtracking activities from recurrent behavior, discuss the impact of the use of multiple windows, and show that in particular infrequently reoccurring activities are poorly supported by current history support mechanisms. We conclude with a discussion on design implications for more personalized history support.