The charge of the Polish lancers at Somosierra Curiosity · Somosierra, Sierra Norte, Madrid Image of Somosierra, not of the place itself. On 30 November 1808 the 9,000 men and 16 guns of Benito de San Juan were holding the pass against Napoleon; the third squadron of Polish chevau-légers, some 150 horsemen under Kozietulski, took it by storm and left Madrid defenceless. Photo: Cruccone (CC BY 3.0) What to see and do in Somosierra