Şömine (from the French cheminée, "fireplace") does indeed have a fireplace, and it offers a warming glow on chilly days. But most diners come in the summer when the air conditioning is a blessing.
Most evenings during the warm months, the linen-clad tables on the open-air terraces at plaza level and on the roof are the choice place to dine.
Wherever you choose to sit, you'll find the menu interesting, the service careful, efficient and attentive, the cuisine excellent, and the prices moderate.
Şömine is at the very center of Ürgüp, in the multi-purpose building at the very center of the town, right next to the small, pleasant park. You should have no trouble finding it.
Reservations are not usually necessary, but they're always advisable to avoid disappointment. Even if you can call only an hour or two ahead of time, it's a good idea to do so just to check on the demand for tables, and to reserve the dining situation (indoors, outdoors) that you would prefer.
Şömine is the most reliably good restaurant in Cappadocia.