This is a list of the places I have visited in both Southern and Northern Ireland over the years. The notes are my opinions only and you might have a completely different view. The prices were correct at the time I visited so it will be worth checking.

Site	County		Notes
Aillwee Cave	Clare		Better than it sounds and well worth a visit. It is much more than a cave, with choices of the cave, a mountain and woodland walk and a birds of prey exhibition. We elected to do the cave only which was expensive at €12 each in 2016! As it turns out, it is actually quite good value including a very interesting 40 minute tour.
Antrim Coast Road	Antrim		A great coast road for scenery. Excellent on a motorbike although suffers a bit by its own popularity.
Ballykeel Dolmen	Newry		Tiny Dolmen down a very narrow lane. If you are passing, have a look, otherwise it is not worth the effort. Free entry.
Baltimore Castle	Cork		More like a big house than a castle, but well worth the visit for both the castle and the village. Baltimore is a pleasant fishing village and the castle stands above the harbour. Very successfully and tastefully restored to its former glory by the owners. Admission charges.
Bantry House	Cork		Bantry House is an inspired destination. There is an inclusive tour that lasts just over an hour and gives a good account of the house. There is a really nice cafe serving coffee and scones with jam and cream. The gardens are also very nice. Worth a visit
Bective Abbey	Meath		Quite a small Abbey and very ruined but it is possible to walk through the cloisters and other sections. Twenty to thirty minutes is plenty. Free entry.
Beltany Stone Circle	Donegal		About five minutes walk from the very small car park. Barely worth it as it is literally a circle of stones about twenty feet diameter. Free entry.
Blarney Castle	Cork		Blarney castle is quite expensive at €15 (2017 price) each and compared to many other Irish castles is simply not worth the money. The grounds are really nice with lots to see and there is an enjoyable walk up to the castle. On my visit there was a huge queue to the top to kiss the Blarney stone. It is not possible to visit the rest of the castle as it is only accessible after the Stone. It took 45 minutes to get to the top up spiral staircases with the occasional empty room. There is no attempt to recreate the castle as it would have been, instead there was nothing in any of the rooms and venturing in simply lost the place in the queue. Kissing the stone involves leaning backwards over the edge and kissing the small stone on the wall. There is of course, a cafe and gardens.
Book of Kells	Dublin		In Trinity College and massively over-rated. The tour includes the Library which make the whole thing worth the €15 entry fee. No tickets are available on the gate, on-line booking only.
Bunratty Castle	Clare		Bunratty castle is well worth a visit. We were there over 5 hours so excellent value for money. The castle is awesome and there are about 25 houses of varying shapes and sizes in the grounds all showing how life was in Ireland. There is even a small village with shops selling all sorts. Entry can be on the door but an on-line booking can be cheaper, even on the day.
Carrick a Rede Rope Bridge	Antrim		Also very over-rated. The bridge is tiny and leads onto an island with nothing special to see or do. Again NT so free to members but not worth the entry fee. Tickets can only be purchased on line so do not turn up hoping to pay on the gate.
Carrickfergus Castle	Antrim		Did not get to see the inside but the outside is very impressive. Would be well worth a visit as the castle is intact and looks to be on several levels. Chargeable entry.
Carrigafoyle Castle	Kerry		Carrigafoyle castle is pretty impressive, being right on the water, although it is now a ruin and locked so not possible to get inside but impressive nonetheless and worth a visit.
Castle Carey	Waterford		A pleasant castle, although not a real castle but a folly. It is reached on foot about 500m from the car park. Worth a visit if you are passing. Free access
Ceide Fields	Mayo		A good visitor centre and an excellent guide really brings alive what is basically a huge field. There are obvious settlement remains and its historical significance should not be underestimated. Well worth a visit.
Charles Fort	Cork		Charles Fort which is on the other side of the bay to Kinsale Town. It is a nice walk with a bit of up and down and mainly off road which is nice. In 2017 there was a €5 entry fee which includes a talk by one of the historians which is very interesting and nicely sets the scene for the rest of the tour. There is a coffee shop on the site. It is a ruined fort but most of the buildings are recognisable and most of the castle can be explored.
Connor Pass	Kerry		A really impressive pass to the Dingle peninsula, well worth the time and effort to do it.
Crom	Fermanagh		It is a National Trust property with a private (no access) castle and a ruined castle. There is a visitor centre with cafe which is okay. The ruined castle and grounds are free access so no need for NT membership. Not worth it unless you want a walk by a lake past a very ruined castle.
Desmond Castle	Cork		Desmond Castle is a Wine museum. The staff are very friendly. The castle was involved in the wine trade and also was a prison so had an interesting and varied history. Well worth the €3 (2017 price) entry fee.
Doagh Famine Village	Antrim		A highlight of the trip! Definitely worth the entry fee of €12 which includes unlimited access to the site, a guided tour and a coffee and scone in the cafe.
Doe Castle	Donegal		A very small ruined castle taking about twenty minutes to visit. Barely worth it unless you are passing. Free entry. There is a small cafe adjacent to the car park.
Dowth	Meath		Barely worthwhile. Imagination is definitely required. Free access.
Drogheda Museum and Tower	Louth		The tower is worth a visit and has some interesting history, allow an hour. The museum is only relevant to Drogheda really so thirty minutes unless you are really interested in history. Entrance fee of €6 for both.
Drombeg Stone Circle	Cork		From the car park it takes about five minutes to walk down to the circle. It is quite small and the rocks only about four feet high but it is interesting with details on a couple of boards. There is also a water pit which apparently had been used for cooking. Worth the trip. Free access.
Dunguaire Castle	Galway		The castle is worth a visit but quite small. Its position makes it easy to find from the road and is very photogenic. It cost €6 each in 2016. There is a small cafe serving coffee and cake.
Dursey Head	Cork		The journey over on the cable car costs €10 (2018 price) and takes less than 10 minutes but feels very unsafe. There are some nice walks on the island and an ancient ruined monastery. The top of the hill has magnificient views all around including the Skelligs in the distance. The main car park has food and souvenir vans. Well worth it.
Elizabeth Fort	Cork		An interesting fort and worth the walk if you are in Cork with time to spare. In 2018 it was a work in progress so hopefully more polished now. Even so, it was well thought out and very accessible.
Four Knocks Burial Site	Meath		Definitely worth the trouble of collecting the key and exploring the inside. The key requires a €20 deposit but otherwise all free. Allow twenty minutes or so to visit the site and probably another twenty minutes to collect and return the key.
Galway Town	Galway		Galway is a very vibrant town with lots going on. The Latin Quarter is full of small cafes and gift shops in small side streets, making exploring fun. The port is worth a visit as is the museum close by. The cathedral is huge and well worth a visit. The seafront walk to Salthill is very pleasant.
Giants Causeway	Antrim		Massively over-rated. I would have been very disappointed if I had to actually pay to go in (it is NT and I am a member). The visitor centre is huge and very comprehensive. The actual Causeway is some distance away but a free Audio Guide helps with the walk. As an NT member, it is worth it, as a paying visitor probably not.
Glen Veigh Castle	Donegal		On my visit the castle was closed so I cannot comment on the inside, but it looks very small. There is a bus service for about €3 each way, but the walk down and back is very pleasant and flat, taking around forty minutes each way. There is a very good cafe at both ends. There are longer walks up above the castle but I did not do them so cannot comment, although given the position I doubt the views would have been much better.
Grannagh Castle	Kilkenny		It is a proper ruin but has a wonderful view of the bridge nearby. The whole castle takes about 15 minutes to see but is worth the slight detour. Free access.
Hill of Skryne	Meath		Just a ruined church, not really worth it.
Hill of Slane	Meath		Worth a visit if you are in the area. Twenty minutes is plenty of time with just a small ruined church and monastery.
Hill of Tara	Meath		Excellent visitor centre brings the place to life, probably better to visit first but the order is unimportant. Visitor centre shows a twenty minute video and the Hill takes around thirty minutes to explore. All free.
Kells	Meath		On my visit, the church was closed (despite notes to the contrary), as was the Saints house and the tower has no access anyway, so very disappointing. If all was open, probably a couple of hours would be needed to see it all.
Kylemore Abbey	Galway		It was quite expensive to get in being €13 each in 2016. The Abbey is okay but there are only a few rooms open. The small church was interesting - it is a cathedral design but really small. There is also a walled garden which is reached by either walking or by free shuttle bus. Allow about 1 1/2 to 2 hours.
Largy Waterfall	Donegal		You need to get there at the right time (low tide) otherwise it is difficult/impossible to access the cave. Definitely worth the effort. Twenty minutes down from the car park and across the beach.
Limerick Castle	Limeric		A real highlight of the tour. It could easily occupy a half day or even longer as there is so much to see. The exhibition gives a full and very detailed account of the Castle and Ireland in general. When we were there (2016) there we real actors and craftsmen acting out characters from the period, so we got to see skilled archers, skilled musicians and nobles of the time.
Loughcrew Cairns	Meath		Definitely worth the walk from the (free) car park up the hill to the cairns. Guided tours are available (free) and well worth it. Allow twenty minutes each way up and down and an hour for the tour.
Malin Head	Donegal		Very touristy and very popular. Be prepared for a walk if driving, unless you are very lucky. Motorbikes are way easier to park. All free access. There is a small coffee seller at the top and the views are incredible.
Mallow Castle	Cork		The castle is in a very poor state and not really worth a visit to be honest unless you happen to be passing through.
Mellifont Abbey	Louth		Definitely worth the time and effort. It is a big site, mostly ruined but there are plenty of explanatory notes and is free to enter. No cafe though.
Newgrange/Knowth	Meath		Should be on everyones bucket list as it was on mine. Personally I thought Knowth was the better of the two as there was more to see, but Newgrange is just incredible.
Poulnabrone Dolmen	Clare		Described as unusually large, it is actually quite small, although I guess by Dolmen standards, big. It is massively over sold of course and attracts all sorts of street sellers. If you like your history and like that kind of environment then pay it a visit, but it wont blow your socks off!
Ring of Kerry	Kerry		An excellent tour around Kerry with many viewpoints and stopping places. Take a couple of days over it and really enjoy the views, villages and stopping places. A must-do for anyone visiting this part of Ireland. The route is free but there are numerous castles and other attractions well worth visiting.
Ross Castle	Kerry		The castle overlooks the lake and is very impressive. Wednesdays are free entry days, plus there is a free guided tour. The castle underwent a lot of restoration over the years and had been well done. The guide was informative and the tour lasted about 45 minutes. There is a coffee shop for refreshments. Definitely worth a visit, even on paying days.
Skellig Islands	Kerry		Everyone should visit the Skelligs once in their lives. It is the most amazing experience ever. Tickets sell quickly months in advance and even with a ticket, the weather can prevent sailing. The trip from Port Magee takes around 50 minutes so you do need to have sea legs. On the island, there is an initial safety briefing before you are let loose to climb the 600 or so steps to the Monastery itself. There is no need to rush, you have around 2 1/2 hours which is plenty of time to listen to the guides talk about the history and then explore the small monastery. There is limited access to other parts of the island quite sensibly. My advice is to stand at the bottom of the steps when the briefing is being given and then head straight up without stopping (if you can). That way, you will have some time to take photos with no one around. There is plenty of time on the way down to photograph the Puffins who are very photogenic.
Skibereen Famine Village	Cork		Skibereen Famine Exhibition is worth a visit, showing a detailed history of the area, especially the time of the famine (mid-1800s) with audio, visual aids, songs, models and reports of the time, plus an interesting video about a local Lough. It is easily possible to spend well over an hour. Also has useful information about surrounding places of interest.
Slieve League Cliffs	Donegal		Definitely worth it. Car drivers have to park and walk. Motorbikes can ride to the very top. If walking, allow thirty to forty minutes each way to the top of the road, then another twenty minutes to walk up to a good view point. It is possible to go right to the cliff tops but a good head for heights is required.
St Brendans Well	Kerry		The nearest place to park is about 15-20 minutes walk away and is proper off road. If its raining, I would seriously consider not bothering as you will get very muddy. I was lucky in that it was dry. The Well is extremely disappointing! It is a hole in the ground with a few crosses and a dubious story. You are going to have to be desperate for history or something to do!
Timoleague Abbey	Cork		The Abbey is a ruin now and in fact a burial ground for the locals. It is well worth the drive to it as it is quite photogenic and interesting to look around. Free access.
Tollymore Park	Down		Very pleasant park with good parking, a couple of cafes and some really nice walks in the forest rewarded by excellent views of the Mourne Mountains. Bike was £2.50, cars slightly more. Definitely worth it if you enjoy forest walking with interesting bridges and good views.
Torc Waterfall	Kerry		Worth a visit if you like waterfalls, but its not huge and not breathtaking. Pleasant walk through the woods just a few minutes from the car park.
Trim Castle	Meath		The castle grounds are free to visit, but the Keep has a fee (€5) and is definitely worth it. The grounds can be explored in thirty minutes, the Keep tour was an hour.
Uragh Stone Circle	Kerry		A real out of the way place and tricky to get to, down very narrow lanes and some off road sections. Barely worth it except for the amazing location which is really atmospheric. Free entry, although there is an honesty box.
Valencia Grotto	Kerry		Seems to be nothing more than an abandoned Slate mine with a Madonna statue. Not worth it unless you are on the island anyway.
Valencia Island	Kerry		A pleasant and very quiet island with few roads. The main town of Knights Town has basic amenities and is worth a visit. There are a number of interesting places to visit, the Grotto and St Brendans Well being two of them.
Waterford Viking Experience	Waterford		Waterford is jam packed with Viking museums and exhibitions. The Viking Experience is probably the best virtual reality experience ever. At €7 (2018 price) proved excellent value. It involves walking inside a Viking house, having a brief chat about the house and Vikings, then watching a virtual reality movie about Viking life which was just incredible. It lasts about 30 minutes and covered their history and really bought it to life. Well worth it.