Architecture is also a significant feature of the Bhutanese identity. The characteristic style and color of every building and house in the Kingdom is a distinct source of aesthetic pleasure. Dzongs (fortresses), Lhakangs (temples), Goenpas (monasteries), Chortens (stupas), Palaces, bridges and vernacular housing that can be seen across the countryside from the diverse but harmonious architectural expressions of the cultural heritage and living traditions of the Bhutanese people. The unmatched combination of engineering skill and aesthetic beauty is reflected in all structures. Traditional shapes, colours and patterns Bhutanese architecture in a class of its own. Among the diverse architecture expressions of the country, the castle-like Dzongs, with their massive stone walls, large courtyards and beautiful architectural details and galleries built on a grand scale without the help of any drawings and constructed entirely without a single nail represent a unique unique architectural marvel.