Ayr used to have an Intercity twice-daily London Euston service (one daytime and one sleeping car train) which ran to/from Stranraer via Barassie to the Glasgow South Western Line, which ceased in the early 1990s. In the 1980s the Royal Scot started from Ayr.
Ayr had a frequent Intercity service to London Euston (one daytime and one overnight) via Stranraer, which closed down in the early 1990s. In contrast, the Royal Scot began its operations from Ayr in the 1980s.