Mount Usher Gardens are one of the best in the world and are a supreme example of the “Robinsonian Style”. Started in 1868, the garden now covers 22 acres (9 hectares) through the middle of which The Vartry River, highlighted by little weirs, runs. There are over 4,500 varieties of trees, shrubs and plants which includes Champion Trees of both Britain and Ireland. It has been maintained without weed killers or artificial fertilizers for over 30 years.