Crawshawbooth and Rossendale are both fairly small and won't take long to explore (which you'll doubtless want to do, given your reasons for visiting). However, if you're driving or using the train, visiting major tourist locations of the north won't be too tricky. As a local, I strongly recommend a trip up towards the Lake District, but the previous recommendations of Liverpool and Chester are also worth a shout! It won't take you long to cross the Pennines and explore Yorkshire, either. All depends on how long your visit is and what you enjoy doing!