It's absolutely worth the visit.
How could a place called "the walled city" not be? Derry~Londonderry is famous for the city walls, as it is the only medieval city wall in Europe that it still completely intact. You can wander along the length of it yourself or join one of the many historic walking tours.
There is so much more to see & do! You could explore the beautiful old library, take in a show at the Millennium Theatre or marvel at the International Sailor Sculpture before crossing the iconic Peace Bridge to enjoy some excellent shopping and admire some magnificent churches & ancient towers before delving into the tales of local history and modern developments at the city murals.
Take a look
here for some detailed information about this beautiful city.