SOMETIMES, a small hotel just won't do. Perhaps you need a ballroom that can show all 3,000 of your wedding guests a good time, not to mention a seat for dinner. Perhaps you'd like to be able to visit half a dozen different restaurants without stepping outdoors. Perhaps you need exercise -- because that's what you'll get if you walk from the door of your room to the front desk of the Sheraton Washington, this city's largest hotel.

There are 1,505 rooms at the Sheraton, the 300 most luxurious of which are found in the 66-year-old wing known as Wardman Tower -- named for the builder of the original Wardman Park Hotel, Harry Wardman. Much of his 1,200- room Wardman Park, which became the Sheraton-Park in 1953, was replaced in 1980 by the sweeping brick structure that now occupies most of the 20 acres on the southwest corner of Woodle Road and Connecticut Avenue.

Besides close to a thousand Sheraton employees, it houses a few other things.

Five kitchens, for example -- one devoted entirely to kosher service. Six restaurants and lounges -- including the Early Light Lounge, with nightly live dance bands, and Wolfgang's Pastry Shop, with its 24 flavors of homemade ice cream.

Then there's the 10 loading docks. The 3,000-seat Sheraton Washington Ballroom. The 900-seat Cotillion Ballroom. A permanent 72-foot convention registration desk. About 95,000 square feet of permanent exhibit space, and 50,000 square feet of meeting space. Two outdoor pools and a sundeck. Thirty-two miles of carpet.

In October, the Sheraton (which is 600,000 square feet total) put on 45 conventions, as many as three of them at the same time. Among its rooms in three separate, attached structures (the main building, Wardman Tower and Park Tower, the last built in 1960) are 125 suites, including two modern $1,200-a-night presidential suites in the main building, and the $1,000-a-night Pearl Mesta Suite in Wardman Tower, with its high ceilings, Chippendale furniture, oriental rugs and crystal chandelier.

Wayne Newton stayed here. Also Bob Hope, Menachem Begin, Lyndon Johnson, Dean Rusk, Douglas Fairbanks Jr. and Gore Vidal.

Checkout time is 1 p.m.

Leave your room by noon and you'll have no problem making it.