Launched in 1964, Madrid's San Silvestre Vallecana is a New Year's Eve 10K street race with artificial snow and fancy dress that attracts some 40,000 runners and revelers. The open "fun" run begins in stages at 5:30 pm near Santiago Bernabeu Stadium, home to Real Madrid FC, on the north side of town and ends at Vallecas Stadium on the south side, a mostly downhill run. The serious runners, limited to 500 and always including some international stars, start off at 8 pm. Dec. 31 is Saint Silvester's feast day celebrated by similar races in other countries and other Spanish towns.

esmadrid.com