If you're in Crowland with 24 hours to spare, there are a few things you can do:
The abbey is a historic building with beautiful architecture. You can take a tour of the abbey grounds, including the ruins of the old abbey and the surviving church. This will take around 1-2 hours.
The trail takes you around the town and showcases its history and notable landmarks. This includes the medieval packhorse bridge, Trinity Bridge, and the Buttercross Market. You can complete the trail in around 2-3 hours.
Crowland is surrounded by beautiful countryside, and it's perfect for long walks. You can go on a countryside walk and explore the area. This can be as short or long as you like, depending on your preferences.
The nature reserve is a haven for wildlife and offers several walking trails. You can take a guided tour, which will give you a chance to learn about the area's ecology and wildlife. This will take around 3-4 hours.
In summary, you can spend a day in Crowland visiting the abbey, exploring the heritage trail, taking a stroll in the countryside, and visiting the nature reserve. You can tailor your trip based on your interests and the amount of time you have.