I believe the Sillman Activity Center just opened last year and it's a really nice place to go for exercise classes or swimming. My wife has gone there for a aerobics class which she liked and we've gone there together to go swimming. The locker rooms are pretty nice with plentiful day use lockers and showers. The pool has up to 6 lanes (I think) though most nights when we went, there was an aquatic aerobics class going on so there were only 2 lanes available for lap swimming. it's a tad pricey ($8 a pop for non-newark resident), but is a nice facility.
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