If you have 2 days to spend in Doncaster, here are some suggestions of things to do:
Doncaster Racecourse is one of the oldest and largest racecourses in the UK, with a capacity of 60,000 people. You can attend a race day or take a tour of the grounds, which usually takes around 1 hour.
Cusworth Hall is an 18th century country house set within extensive landscaped parklands. As a visitor, you can explore the house and gardens, which usually takes around 2 hours.
Conisbrough Castle is a 12th century castle with a famous circular keep. You can climb to the top of the keep and enjoy views of the surrounding countryside, which usually takes around 2 hours.
The Yorkshire Wildlife Park is a large wildlife park with over 400 animals and 70 species. You can see everything from lions and tigers to meerkats and baboons, which usually takes around 4 hours.
There are plenty of hotels in Doncaster, such as the Holiday Inn Doncaster A1 (M), which is located just off the A1 motorway. You could also look at renting a cottage in the nearby countryside, such as one of the properties offered by Sykes Cottages.