Driver allegedly four times over limit

A man has been charged with high-range drink driving after he was allegedly caught driving four times over the legal alcohol limit in Sydney's north.

Police say they were alerted at about 8pm on Thursday that a car was travelling dangerously along Mona Vale Road at St Ives.

A witness followed the vehicle to Turramurra where they approached it as it was stopped at traffic lights and removed the keys.

Police arrested a 68-year-old man who underwent a breath test analysis which returned an alleged reading of 0.226.

The man had his licence suspended and was charged with high-range drink driving and granted conditional bail to appear at Hornsby Local Court on November 24.