62190
The seat of the county was initially at the castle of Curiel and later at Monteson ; to its east the river Pisuerga served as a border with the County of Castile .
 Curiel, Monteson, Pisuerga, Castile
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Curiel, Monteson, Pisuerga, Castile