GRAMMAR'S RESPONSE. The word premises is always plural, whether you're referring to the whole of the land and the buildings upon it or just part of the mall (or whatever). So you want are, always. Authority: Merriam-Webster's Collegiate Dictionary, Electronic Edition, Version 1.5.
Yonne is a department in the centre of France, in the Burgundy region. The largest city in the department, and its prefecture (capital), is Auxerre.
Yonne. Named after the river Yonne, which flows from the centre of France, northwards and into the river Seine. The Yonne is to the south-east of Paris. The regional capital city of Auxerre is a worthy visit for all visitors.