During this stage of the 2020 Covid restrictions we were limited to Dublin county only. We decided to view some of the opportunities in the northern Dublin Mountains, some parts of which I hadn't visited for 30+ years.
The route starts with on street parking near Kilgobbin Cemetery in Stepaside where there is a small amount of parking. To access the uplands from here, use the right of way through the Fernhill Estate emerging at Barnacullia, near the Blue Light, one of Dublin's great and mostly undeveloped pubs.
There's two routes to the mountains here, one to the north of the Blue Light, one to the south. We took the south first and returned via the north. Follow the tracks as shown and eventually you will reach the Three Rock area. Halfway up Fairy Castle we took a west turn which had far fewer than the much greater than average crowd on the better known routes.
Proceed to Tibradden. We stopped to survey the col height at the col SE of Tibradden. The top of Tibradden has a huge view over Dublin and also over the rest of the Dublin Mountains into parts of northern Wicklow.

For variety we returned somewhat north west of the our outward route.

This included this less travelled track directly east of Tibradden. The final return was via the highly developed area SE of Ticknock where there are the remains of a rifle range and some elaborate MTB routes. Back to the Blue Light on a route near but not through an active quarry. Look very carefully at the route since there is a maze of small paths, not all going the right way.