We will be in Dublin for 2 days. However, we have booked a tour to Newgrange though Mary Gibbons tours for the second day of our visit and from what I understand that will take up that whole day. On day 1, which will be the day of our arrival from US, we would like to do our city sightseeing. What we'd like to see for sure is Kimainham Jail, Trinity College, St. Patricks Cathedral, & possibly Guinness Storehouse. We would, also, like to do some "dandering" I believe it's called. How much time would the above sites take to adequately see and is all of that way too ambitious for the day we arrive (considering jet lag) - which BTW is a Monday in case that is significant.
One other question, is the Dublin Pass worth it for one day and the above itinerary? I don't believe it covers the Trinity College and we may not make the Guinness Storehouse. So the main thing that makes the Pass glamourous to me is going to the front of the lines but that may not be an issue in Sept. on Mondays.