Aguas Calientes 
the town under Machu Pichu
I think the name comes from the Spanish for hot water, but don't trust my translations.
The town is described by some as rather touristy, as though the writers just happen to be there on important business, rather than being tourists. Personally I found it charming.
The roofs are often corrugated iron, obviously used over and over again, eventually becoming proper tiles as the building is completed, and handed on to the next builder. As the place becomes more up to date and professional, it will inevitably become more ordinary, but it is being done with a degree of care, and should retain most of it's slightly quirky  "border town" feel.
It has a huge and interesting market for T-shirts, hats and all the touristy stuff, including the Peruvian silverwork and jewelry one would expect. 
There are loads of restaurants,  I would advise you to settle your bill early if your train is leaving soon, these people do not all speak English, also there are three or four currencies to deal with. My Spanish is nonexistent and Quechua is totally different anyway, you can't even use Latin to keep you afloat.
Good hotels are easy to find and worth using instead of rushing in and out in one day, which doesn't do the place justice, let alone Machu Pichu, and of course there are the hot pools. These are a series of various temperature pools, they don't smell too bad and even in the rain are well worth a visit.
The fossil and I decided to pass on the second visit to Machu Pichu and go for a dip instead. It's a long walk up a moderate slope to get to it There are seats to rest on if you feel so inclined, (remembering the altitude), and you can hire a towel at the top. The shop outside is cheaper than the ticket office, though neither could be described as expensive. 
John came along as well and so you get the special treat of a photograph of your humble scribe with his mother, I think from my expression she had made a cutting remark of some kind.
After our soak we were rained on a bit, just so we could appreciate at least an idea of what the torrent could get like, so we adjourned for a beer. While there the townsfolk used the railway as a street, the old platform having become a series of shops and restaurants some years before.
Aguas Callientes is a charming and interesting place, and Gringo Bill's is the place to stay. Take my word for it. If you are visiting Machu Pichu take at least two days and see both, it's a long way to go so do it properly.