Simplify the following text for a Grade 3 native English-speaking person.
Original: Originally enclosed by a picket fence , then by a wrought iron fence and gates in the 1870s , the space was opened with the removal of the fence in 1939 .
Simplified: In the 1870 's a new wrought iron fence and gates were built . The space was opened when this fence was taken away in 1939 .