We have visited this Ayrshire town twice or three times over the past couple of years (and the adjoining Eglinton Country Park as well although the rain on that occasion meant we didn't stay long!)
Kilwinning is particularly known for having the original Lodge of the Freemasons, seen below.
Kilwinning is known as the 'Crossroads of Ayrshire' and it's a great place to travel from as you can get everywhere easily by train!
This is a wonderful old ruin, all that's left of the abbey since most of it was pulled down in 1562. A church is thought to have stood on this site as early as 1157, but the major part of the building was created in the 13th century. What remains today is still very impressive. The abbey is on a rise overlooking the River Garnock in the centre of the town, immediately off the pedestrianised shopping street - and free to visit too!
The Wikipedia website has all the history of the abbey here and you can find out much more about the town here