Staining Chesnut doors

I have a number of lovely chestnut doors in the house. A couple are looking tired, and I suspect one may actually have been painted at one stage prior to our ownership of the house. 

Can anyone advise of an oil or stain I can use on the doors to "brighten" them up??

Thanks

We stripped and stained all the chestnut in our 1920's home last year. We tried several stains and found the one that best brought out the chestnut color was Minwax Old English Chestnut.