Graphics[{
Gray,EdgeForm[Black],CountryData["UK","Polygon"]
}]

CountryData["Europe"]

Graphics[{
EdgeForm[Black],LightGray,
(Mouseover[
CountryData[#,{"Polygon","Mercator"}],
Tooltip[{Gray,CountryData[#,{"Polygon","Mercator"}]},#]
]&)/@Complement[CountryData["Europe"],{"Svalbard"}]
},AspectRatio->Automatic,ImageSize->500
]