Since the late 1990s, some carrel desk designs provide AC power and Ethernet receptacles for students using laptop computers. Like the school desk, the carrel desk is normally produced and sold in large quantities for an institutional market. They are made to stand alone or to be grouped together, with or without common sides or walls. The word carrel can also refer to a small isolated "study room" in public libraries and on university campuses; usually the room has a lockable door to which the user is granted the key on request. Carrels usually contain a desk (not necessarily one described as above), shelving and a lamp. Carrels are generally quite popular at universities and are therefore usually quickly occupied. This becomes especially true during mid-term examinations and finals. They have the advantage of power for a laptop (and often internet port) as well as generally being quieter than in the main library building. Carrels are also often used as temporary storage for books and materials the user is not finished with while they are at lectures or labs. Carrels originated in monasteries to help contain the cacophony of roomfuls of monks reading aloud, as was the early practice. Carrels are first recorded in the 13th century at Westminster Abbey, London, on the garth side of the North Walk, though they probably existed from the late years of the 12th century. Brockwell Park  Brockwell Park is a 50.8 hectare (125.53 acres) park located south of Brixton, in Herne Hill and Tulse Hill in south London. It is bordered by the roads Brixton Water Lane, Norwood Road, Tulse Hill and Dulwich Road. The park commands views of the skyline of the city and Central London, and hosts almost 4 million annual visits. At the top of the hill within the park stands Brockwell Hall. Whilst competing against multiple demands from a broad range of other interests, the entirety of Brockwell Park is a Site of Importance for Nature Conservation (SINC) of Borough Importance (Grade I), with mature trees including ancient oaks, substantial lawn areas set to meadow, and a series of lakes. As well as adding to the landscape value, these support a variety of birds, and bats including Pipistrelles, with frequent visits from rarer species like Daubentons, Noctule, Leisler's and Serotine bat. The Park is listed for its heritage value on The National Heritage List for England, Parks & Gardens, Grade II.