That depends on when and what you're looking to do there.
It really depends on the season you are visiting and your purpose. In general it's a good place in all seasons if you practice general safety.
It's a good place for kids depending on what events are happening there (fountains, movie nights, etc). You may have to pay for food generally, but there are bathroom facilities inside City Hall, which is pretty secure and easily accessible.
Summertime
It would be fun for that age to play in and around the fountains but if might be tough to have an organized event like a party. This is also a grassy spot if you wanted to lay out a blanket.
Yes , its a good place for any age. Depends on what type of fun you are tying to have but sure you can
Yes
Yes it is.
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