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3. Rock FallsRock falls are an ever present hazard along many parts of the Co. Antrim and Co. Londonderry coasts especiallywhere principal road and rail routes run along the narrow strip of land between the shore and the edge of thebasalt plateau. Rock falls have been a regular occurrence on the Antrim coast road where steep and overhangingbasalt faces require ongoing management and often have to be removed or secured using geotextile nettingand rock anchors.Along the north coast, the Belfast to Londonderry rail track, which runs on a narrow coastal strip betweenCastlerock and Downhill Strand, has proven particularly vulnerable to rock falls. A recent event (June 2002)resulted in derailment of the Londonderry to Belfast passenger train. (http://www.niassembly.gov.uk/record/reports/020610.htm#2).Landslide Hazard Assessment on the Antrim CoastThe overall landslide hazard along the east Antrim coast was assessed in research carried out by the BritishGeological Survey (Forster, 1998) on behalf of the Geological Survey of Northern Ireland.Geological and engineering geomorphological mapping techniques were used together with aerial photographicinterpretation and an understanding of landslide processes to categorise the landslide types. Land with similarlandslide hazard levels was then zoned on the basis of estimated landslide risk (low, medium, high, and veryhigh levels). The research described constraints to land use and development within the various hazard zonesand could potentially be developed to provide a decision support tool for land use planners.Fig. 7.3 Mudflow and Rock Fall Localities on the east Antrim Coast (from Prior et al., 1971).75