Nomahegan Park in Cranford is gorgeous, with the rahway river winding through it (and the town). They also hold the Union County music fest in it I believe.
spring 5d_2007-04-22_016 on Flickr - Photo Sharing! (http://www.flickr.com/photos/scubapup/469170377/in/set-72157600147497609/ - broken link)
spring 5d_2007-04-22_017 on Flickr - Photo Sharing! (http://www.flickr.com/photos/scubapup/469158164/in/set-72157600147497609/ - broken link)
spring 5d_2007-04-22_035 on Flickr - Photo Sharing! (http://www.flickr.com/photos/scubapup/469178271/in/set-72157600147497609/ - broken link)
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Far From Home on Flickr - Photo Sharing! (http://www.flickr.com/photos/snowdog101/2543263421/ - broken link)
spring 5d_2007-04-22_019 on Flickr - Photo Sharing! (http://www.flickr.com/photos/scubapup/469172569/in/set-72157600147497609/ - broken link)
little man on Flickr - Photo Sharing! (http://www.flickr.com/photos/scubapup/2435602103/ - broken link)
Panoramio - Photo of Nomahegan Park