You can buy a combined ticket with the Roman Baths that will also get you into the Assembly Rooms and Costume museum. It's well worth it as these are the top two attractions in Bath. On it's own, it costs £7.
There is a cafe open in the afternoons and there is of course a gift shop. You are allowed to take photographs though the Costume museum is dark and the costumes are behind glass so it won't be all that successful here.
Assembly Rooms:
It is a very fine example of Georgian interior with amazing plastered ceilings and opulent 18th century crystal chandeliers. There are three main rooms, the Octagon Room for playing cards, the tea room for light refreshments and the ballroom where dances and concerts were held. You can hire the tea room and ballroom now for private functions and it looked as if they were being set up for something. Each room had a gallery above the floor level for musicians to play. The website for the Costume museum has a good history of the building under the Assembly Room links. The building is wheelchair accessible with ramps and lifts.
In the same building downstairs is the Costume museum which I really enjoyed. They have clothing and accessories from as far back as the 16th century with the oldest complete outfit dating from 1660. The blackwork embroidery on one shirt from the Elizabethan era used silk so fine you couldn’t’ even tell it was stitched. Everything that old was of course sewn by hand, though some could still be quite elaborately decorated. The designs themselves became more elaborate with things like pleats and ruffles after the invention of the sewing machine in 1846. They had men’s and women’s clothing, shoes, fans, under garments, gloves and accessories. Most of the collection is pre-Edwardian with a smaller collection from the 20th century to modern age. The modern things don’t have very much explanation on the audio commentary, which was identical to the kind used in the Baths.
The museum had a "doll" about 18 inches tall, headless, with a Georgian court dress, the kind with the very wide pannier type "baskets" over the hips that gave the wide rectangular shape skirt, probably a good 5 or 6 feet wide from side to side on a full size dress. They used the dolls as "catalogues", to show what the dress would look like before it was made. They had a mannequin wearing a similar dress in the same case. Another item that caught my eye was a corset from the Edwardian era that would have pulled and manipulated the female shape into the "S" fashionable shape and the waist seemed pulled in almost to the point where I could probably have got most of my hands around the waist. It made me shudder to think what women did to themselves for fashion. And still do.
From journal Magical History Tour 2003