Simplify the following text for a Grade 4 native English-speaking person.
Original: TrenÄ Ã n Castle , a typical medieval fortified castle is situated high on a rock above the city . TrenÄ Ã n is best known for a Roman inscription on the rock below the TrenÄ Ã n Castle dating from 179 AD , the era of the Marcomannic Wars , a series of wars between the Roman Empire and the Germanic Quadi .
Simplified: TrenÄ Ã n is best known for Roman writing below the TrenÄ Ã n castle .