Start with the thing most guides get wrong. The Suir Blueway is often described as a cycle route from Cahir. It is not. From Cahir the Blueway is a 53km paddling trail to Carrick-on-Suir. The waymarked, traffic-free walking and cycling section is the 21km towpath between Clonmel and Carrick-on-Suir, twenty minutes away by car. The only traffic-free riding at the Cahir end is the 4km path between the castle and the Swiss Cottage, which is a walk more than a ride.
So cycling from Cahir means road cycling. Fortunately the roads here are good.
The Blueway, properly
If you want the flat, traffic-free family day, drive to Clonmel or Carrick-on-Suir and ride the towpath. It is 21km one way along the river, easy the whole way, and an average cyclist covers it in under two hours. Treacy's Blueway Bike Hire at North Quay in Carrick-on-Suir hires adult and children's bikes, e-bikes, trailers and safety gear, which makes Carrick the easier end to start from if you are not bringing your own.
Doing it one way and arranging a lift back is more pleasant than doing it twice.
Road riding from the town
Cahir sits in a basin with the Galtees to the west and the Knockmealdowns to the south, and the lanes between them carry very little traffic once you are off the national roads. The riding is rolling rather than flat, and the surfaces are variable in the way Irish back roads always are.
Three obvious directions:
- South to the Vee. Over the Knockmealdowns through the Vee gap towards Lismore. This is the serious climb of the area and one of the best road ascents in Munster. Long, steady, and spectacular at the top.
- West into the Glen of Aherlow. Around or through the shoulder of the Galtees into the glen, which is a quieter valley with good roads and the mountains directly overhead.
- East along the river. Towards Ardfinnan and Newcastle on small roads following the Suir valley, which is the gentlest of the three and the best if you want distance without climbing.
Avoid the N24 and the old N8 where you can. They carry the traffic that the motorway does not.
What to know before you go
There is no bike hire in Cahir itself. If you are not bringing a bike, the hire is at Carrick-on-Suir, which shapes what is realistic.
Take what you need with you. Once you are into the lanes there are few shops, and phone coverage in the glens is patchy. Irish weather does what it does, so carry a jacket even on a good morning.
Off road
Scaragh Wood and Glengarra Wood are both forestry with waymarked trails, and while they are walking loops rather than bike trails, the forest roads within them are rideable on a suitable bike. Walking near Cahir covers both properly.
Afterwards
Cafes in Cahir for the coffee, pubs in Cahir and the restaurants for afterwards, and things to do in Cahir for the days you leave the bike alone.