I.over [美 ˈoʊvər, 英 ˈəʊvə]副over often appears as the second element of certain verb structures in English (blow over, knock over, pore over, etc). For translations, see the relevant verb entry (blow, knock, pore, etc).
All the rivers freeze over and locals actually do river crossings during this period because their high levels from glacier melt in summer inhibits crossing.