Opened in 1796, Kilmainham Gaol was the county gaol for Dublin at the time and it had its doors open until 1924 when it was shut down, now it is open to public tours where you get to walk inside and see and feel what it is like to be inside Kilmainham Gaol.
We visited the gaol in 2016 when we visited Ireland and if you will only be in Dublin, I would say that it is worth a visit. When we were there, they were celebrating the 100th year of the Easter Rising and it was actually fully booked, so we had to make sure that we bought tickets ahead of time, I'm not sure if that is the case anymore, but just a word of caution.
Having visited the Crumlin Road Gaol in Northern Ireland, we were a bit let down by this one. It has to do with the pace in which you are escorted around in my opinion, you were constantly rushed from one point to another. However, there are a lot of cool looking sights if you have never been to a gaol before.
For those interested, visit the official website for more details at http://kilmainhamgaolmuseum.ie/
Come back next Friday for another Past Point of Interest!