Complex sentence: In 2001 it was once again renovated, with fountains and ponds it was once again an impressive small park, but 6 years later, in 2007 it was once more run down, due to lack of maintenance.
Split into simpler sentences: In 2001 it was once again renovated, with fountains and ponds which made it was once again an impressive small park. However, 6 years later, it was once more run down, owing to lack of maintenance.