United Kingdom, April 14 -- Alstom, global leader in smart and sustainable mobility, is delighted to announce that Nottinghamshire-based painter Tim O'Brien will be the official artist in residence for The Greatest Gathering in the UK.Alstom's three-day festival in Derby forms part of the wider festivities for Railway 200, a year-long celebration marking the opening of the Stockton and Darlington Railway (S&DR) on 27 September 1825 - and a journey that gave birth to the modern railway.Thousands of visitors coming to The Greatest Gathering will get to see Tim painting 'en plein air', as he captures the rolling stock, atmosphere and architecture on show at Britain's biggest rail celebration.Tim, an award-winning artist, author and tutor was b...