A 3′ W x 18″ D x 4′ H shelf unit sits on one side of the closet. Most shelves have several bins, each dedicated to a different activity or item. We actually have one bin that only stores gloves (we like warm hands).
The top shelf has wire baskets: one for maps and paper items, one for travel organizational items (like space bags and packing cubes), and one for miscellaneous small items like compasses, sunscreen, head lamps, etc.
The bottom shelf holds boots and a bin for shoe-related items (crampons, gaiters, traction devices, etc.)
The top shelf, built into the closet, holds sleeping bags (we keep these unpacked to preserve loftiness and effectiveness) and other large and bulky items.