The revamped Doncaster Racecourse is to reopen following a £32m facelift.
Finishing touches were put in place ahead of the reopening
Officials said the trial day at the South Yorkshire course would aim to iron out any problems ahead of the St Leger Festival in four weeks' time.
The historic site has been completely transformed since closing in December 2005 for the 21st Century revamp.
About 10,000 people were expected to attend the racecourse on Friday, with a crowd of more than 30,000 expected for the St Leger on 15 September.
The old grandstand, built in 1969, has been replaced by a five-tier structure with all but the top floor open to the general public.
The Urban-i stand includings a conference and exhibition centre, betting outlets, bars, dining areas, private boxes and hospitality suites.
The historic site was redeveloped in a joint venture by Doncaster Metropolitan Borough Council and Arena Leisure.
Marketing manager Jo Mapletoft said: "We've been closed for 20 months so it's important we get this trial meeting to make sure everything is in working order for the Leger.
"It's going to be a whole new experience and a new era for us. Things are so different."