Most of the directions below will take you to Exit 18 on the M8 Cork / Dublin road.

From Dublin 1 h 59 min (210 km)
Follow M7 and M8 to R639 in Cork. 
There is a Toll at Watergrasshill - about 3 Minutes away from the circuit.
Take exit 18 from M8
Follow the signs, you're only about 1 Minute away
Committee Note .... Don't forget to put up the signs :)

From Rosslare - 2 h 30 mins (186 km) 

Make your way from Rosslare, Wexford, New Ross, Waterford to Dungarvan. You now have two choices... (A-  Better Road, B - Shorter...ish)   
A. (77 Km) Dungarvan - Youghal, Killeagh, Midleton, Carrigtwohill 

B. (69 KM) Dungarvan - Cappoquin, Lismore, Tallow, Conna, Rathcormac, Watergrasshill. 

Dungarvan - Youghal, Killeagh, Midleton, Carrigtwohill, Dublin Road.
At the Roundabout before the Tunnel just outside Cork, take the Dublin road.
Take exit 18 from M8 & follow the signs - Only a few minutes away.
(Roundabout before the Tunnel ** Do not go through the tunnel !)
 

From Limerick - 1 Hr 25 mins (97.3 km) Mitchelstown, Fermoy - via the M8
Take R512 and R513 to Mallow - Dublin Rd/N73 Cork
(Thats not to Mallow, just the 'Mallow/Dublin Rd)Take M8 to R639.
Take exit 18 from M8

Follow the signs, you're only about 1 Minute away.
You don't need a map, The one above will do from Rathcormac :)
 

From Cork -The City (16 Min 14 km)

Take the lower Glanmire road, past the train station, Tivoli & Silversprings out small two lane straight  to the 'Glanmire' roundabout.
Continue to the 'Dublin road' Roundabout (Don't you go under the tunnel either !!)
left lane, left turn onto the Dublin road.
Take exit 18 from M8 & follow the signs.

From the 'South Side'

Take the link road and DO go under the tunnel, Take the Dublin road and then
Take exit 18 from M8 & follow the signs.
The circuit is only about 5 Mins from the 'Tunnel Roundabout'