Complex sentence: On the weekend starting 25 May the railway operated a special service.It now runs trainsservices every weekend and Bank Holiday in the summer; during the Olympics in July/August 2012 at nearby Stratford, the line operated daily.
Split into simpler sentences: On the weekend starting 25 May the railway operated a special service. Epping Ongar Railway now runs regular services every weekend and Bank Holidays in the summer; during the Olympics in July/August 2012 at nearby Stratford the line operated daily.