I visited Belfast for a second time last year (2012) and this time I did the "Black Taxi Tour" and it was very interesting. The driver was part of the Catholic community and he drove me through both the loyalist Protestant areas (i.e., Shankill Road) and the Nationalist enclaves (Falls Road and Bombay Street). One of the most surprising parts of the tour was to pass by the "Peace Lines". I had no clue Belfast had built those walls during the troubles to separate Catholic and Protestant neighbourhoods. In this picture you can see one of those walls along Cupar Way in Belfast.

The only time I have been in the "North" (Northern Ireland, for the locals) was in November 06. One of the most interesting parts of the trip was going to the "Giant's Causeway", where the lava formations created these particular shapes that you can see on this picture.