At low tide you can come to Llanddwyn island from the Malltraeth side of Newborough beach. You don't need to climb up the rocks but you can go through the gates. They have been installed to keep the horses that are grazing on Llanddwyn island there and keep them from running away at low tide.

Gates to Llanddwyn island - Newborough visitor guide showing a virtual tour of 'Gates to Llanddwyn island' linked to an interactive map with local and travel information. 360° panoramas from Anglesey.