74717
A crucial factor in their popularity was the development of the long-range railway network , which allowed the transport of herring from the North and Baltic seas to the interior .
 North, Baltic
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 North, Baltic