Ljubljana's sights are compact and best explored on foot. The old town runs east from the Triple Bridge along the right bank of the Ljubljanica. The castle on the hill above it has the best views. Presernov trg (Preseren Square) and the Triple Bridge are the social centre of the city. Architect Joze Plecnik's work is everywhere — the covered market, the Triple Bridge extensions, the National and University Library — and gives the city a distinctive Central European modernism unlike anywhere else.