I have to visit some of the following cities in NJ, would you pls inform which ones are closer to Hackettstown ?

Upper Montclaire
Guttemberg
Northfield
Woodbridge
Dernellen
Lydhurst
Medford
Paramus
Summit
Middleton
Verona
Caldwell

Thanks for your help.

A map might help.
I don't think anyone of them are "close" to Hackettstown.H is near the Del Water Gap/Pa.

I don't think any are too close to Hacketstown, which is in Western NJ.

However, the following towns are somewhat close to each other (within ~15 mile radius):

Upper Montclaire
Guttenberg
Woodbridge
Lyndhurst
Paramus

Paramus is about 50 miles east of Hackettstown in Bergen County and Guttenberg, a small town in Hudson County, is about 60 miles east of Hackettstown...Lyndhurst and Upper Montclair aren't too far from the Paramus area...interesting assortment of towns in various areas...Hackettstown is convenient to major NJ highways such as I-80, Route 46, and the Garden State Parkway.

Your spelling is way off. Here are the correct spellings so you can check them out on Mapquest.
Guttenberg-In Hudson county-very small between West New York and North Bergen-it may not even be on a map.
Dunellen-In Middlesex county near Summit
Lyndhurst-in Bergen County-near Paramus
Middletown-In Monmouth County not far from Raritan Bay-its heading to the shore area.
None of them is near Hackettstown. You are closer to Pennsylvania when you are that far west.

From the GWB to Hackettstown is about an hours drive.maybe 45 minutes if you don't hit traffic.