There are beautiful walks and views in the area, that pass a number of renowned tourist sites.
Howth Cliff walk
One of the nicest walks in easy reach of Dublin. Get the Dart train to Howth village (about 25 minutes from the city centre), turn left and walk past the harbour (also a lovely walk and has a great restaurant called Aqua).Keep following the coast and you will find yourself on a wide unpaved path that runs along the southern part of Howth Head. Get ready for a bracing walk with fantastic views over Dublin Bay on a nice day. If you keep walking for two to three hours you eventually arrive in Sutton. Keep walking along the coast and you will end up at the Marine Hotel. You can get back to Dublin from the Sutton Dart station.