The smell is unbelievable. As you enter the tannery, you are greeted with a gentleman who kindly passes visitors fresh stalks of mint. The smell does not get really bad until you've reached the 4th floor, from where you can see the tannery below from the balcony. It is much more effective to crush the mint and insert it into the nasal passages than to just smell the mint like a flower (as I did). Fortunately, the temperature outside was cloudy and not too hot today, otherwise the smell would have been 100X worse! Worth the visit, none the less.