Boathouse And Tandem Location.
This location was seen twice in the film. First after Sean and Mary Kate had taken the tandem from outside the Reverend Playfair's house, they rode past Pat Cohan's Bar and round the corner. When we see them again they come round from the right of the picture past the boathouse and down the road. The next time we see this location is when Sean is walking Mary Kate back from the Dublin train on his way to claim his wife's money from Danagher.
To get to the locations outside of the Cong area take the road west out of Cong by O'Connor's Petrol Station and head for Cornamona.