Ard Mhacha,
If you don't mind me adding some information as well - Ard Mhacha was also supposed to be the capital of Ulster in ancient times, a palace was according to legend built by Mhacha about 400 BC or so, and stood until around 400 AD or so when it was destroyed by an invasion led by tribes from Connacht. Our English colleagues may recognise the area if we use the more familiar name Armagh :)