Hi
I know Donegal pretty well, having had holidays staying at my wife's family's home in Dungloe over the last 30 years. Depending on your kids' expectations and interests, and assuming that the weather will be 'variable', there are many different things to do and experience, particularly if you like more leisurely, non-technological and outdoors pursuits. Remember that Donegal is by Irish standards a big county, with relatively poor road net and virtually non-existent public transport, and travel can take longer than you might think. For instance Dungloe to Letterkenny takes a little under an hour; Dungloe to to Donegal (Town) will take about an hour, but Donegal Town to Malin Head could take 3 hours....Things to do in no order:
- Finn Valley Railway, a heritage railway, in a beautiful valley with Lough Finn alongside. Note only open until mid-September.
- Walk up close to, or up on to (if the weather forecast is fair) Mt Errigal
- Visit Glencolumbkille - if you can, get there by driving up the Glengesh Pass (road from Ardara to Glencolumbkille)
- Near(ish) to Glencolumbkille is Slieve League - reputedly the highest sea-cliffs in Europe.
Donegal Town is probably the most touristy spot in the county, but it is worth a visit - castle, abbey, railway museum, tweed shop (Magees) and quite picturesque. Letterkenny is best place in the county for retail stores though. Near Letterkenny is Newmills Corn and Flax Mill.
Malin Head is most northerly point in Ireland; also in the north of the county are Dunfanaghy Workhouse; Glenveagh castle (really a small stately home) plus its extensive, wild and beautiful national park (deer and eagles); Rathmullan heritage centre (on scenic Lough Swilly); Fort Dunree (originally a British fort, guarding the Swilly Naval anchorage); Doe Castle and so on.
The coast line right round the county, west and north, is absolutely breathtaking - the Wild Atlantic Way is well signed, but if you're braver, take some of the smaller roads wherever 'Tra' is signed - you will inevitably find truly great beaches, which are generally pretty deserted. Remember though that facilities at them will be non-existent for the most part.
You should also consider checking out Derry/Londonderry City just over the border in the UK and, as I discovered just last month when I visited, the Marble Arch Caves, near Enniskillen - magnificent limestone river-cut caves that include a boat ride underground.
And I haven't mentioned sports, walking or music! Just remember to bring a good book or two also, in case the weather is bad for a few hours one day.
Enjoy!