Possible Clues:

• A harvest grain store up in old citadel
• Greek citadel
• This defence was made up in Athens
• Carol is struggling round river in Greek citadel
• Citadel has a harvest store put up
• What the farmer reaps on the soil of at hens
• A harvest and place to store it back in citadel
• After a harvest, grain store turned into a place of high security
• Pool car is repaired in the citadel
• At hens farmers may get a yield from such soil