You should pull up and remove weeds by hand as and when they appear. If it is a regular problem, you might need to reseal the paving. In extreme cases, the sub layer itself may need to be re-laid. You can use weed killer, however some paving can be discoloured by stronger weed killers.
Castlederg
Castlederg is a village in County Tyrone, Northern Ireland. It rests on the River Derg and also is near the boundary with County Donegal. It stands in the townlands of Castlesessagh as well as Churchtown, in the historical barony of Omagh West as well as the civil church of Urney. The village has a ruined castle as well as two old burial places referred to as the Druid's Altar and Todd's Den. It had an estimated population of 2,935 individuals in 2008. The town organizes a few of the district's crucial events yearly, including the Derg Vintage Rally, Dergfest music festival, Derg Soapbox Derby, Red River Festival as well as the conventional Apple Fair which sees the apple growers of County Armagh see to sell their merchandises. Commonly, Castlederg was a traveller's quit along the old pilgrimage path to Station Island on Lough Derg. The community flaunts old damages as well as reclusive settlements.