Sierra Morena

Sierra Morena, a mountain chain in South Spain, forming the watershed between the valleys of the Gaudiana (N.) and Guadalquivir (S.); has valuable deposits of lead, silver, quicksilver, and other metals.

Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)

Sierra Madre * Sierra Nevada
[wait for the fun]
Sidney, Sir Philip
Sidon
Siebengebirge
Siegfried
Siemens, Werner von
Siemens, Sir William
Sienna
Sierra
Sierra Leone
Sierra Madre
Sierra Morena
Sierra Nevada
Sieyès, Abbé
Sigismund
Sigismund
Signorelli, Luca
Sigourney, Mrs.
Sigurd
Sikhs
Sikkim
Silage