This paper presents a comprehensive reliability analysis of a modern onshore wind farm, leveraging the integration of SCADA data, alarm logs, and maintenance work orders to assess fleet performance over a two-year period. A robust data harmonisation and cleaning process enabled the identification of high-confidence corrective maintenance events and the calculation of key reliability indicators, including failure rates, downtime, and technical availability. The studied fleet achieved a high technical availability of 99.96% and a normalised failure rate of 1.22 events per 10,000 operating hours, in line with industry benchmarks. Analysis revealed that a small subset of turbines and five critical subsystems accounted for the majority of downtime, highlighting opportunities for targeted condition monitoring and preventive maintenance. The findings offer actionable insights for wind farm operators and lay the groundwork for future enhancements through more advanced methods of data analytics.