On Paris's highest hill whiten the Sacré-Cœur domes — from its steps the city spreads as a sea of gray roofs: behind, Montmartre with the painters' Place du Tertre and the lanes Picasso and Van Gogh inhabited. The funicular climbs on a metro ticket for the stair-weary; an instant portrait at the painters' square is authentic Parisian memorabilia — price agreed before the brush; mind the wrist-string game below the steps — a firm non merci and walk.