The Alps are popular both in summer and in winter. The Alps as a place for sightseeing and sports. Winter sports (Alpine and Nordic skiing, snowboarding, tobogganing, snowshoeing, ski tours) can be learned in most regions from December to April. In summer, the Alps are popular with hikers, mountain bikers, paragliders, and mountaineers. There are also alpine lakes which attract swimmers, sailors and surfers. The lower places and bigger towns of the Alps are well served by motorways and main roads, but higher passes and by-roads can be bad even in the summer. Many passes are closed in winter. Many airports around the Alps (and some within), as well as long-distance rail links from all bordering countries, afford large numbers of travelers easy access from abroad. The Alps normally has more than 100 million visitors a year.