By road: Driving instructions are available here
By bus: From Northern Ireland, Ulsterbus run regular services to and from Derry. From Belfast it is about 1.5 hours and buses leave roughly every 30 mins. More info at www.translink.co.uk
From the Republic of Ireland, Bus Eireann connects directly from Dublin, Donegal and Sligo. Visit http://buseireann.ie for details
Airporter run a direct transfer service into Derry from all three airports.