months (March and April) see variable conditions, with a rapid increase in the average temperature. The weather in late March and in April is often very agreeable during the day and fresh at night. Budapest's long summer – lasting from May until mid-September – is warm or very warm. Sudden heavy showers also occur, particularly in May and June. The autumn in Budapest (mid-September until late October) is characterised by little rain and long sunny days with moderate temperatures. Temperatures often turn abruptly colder in late October or early November. Mean annual precipitation in Budapest is around . On average, there are 84 days with precipitation and 1988 hours of sunshine (of a possible 4383) each year. From March to October, average sunshine totals are roughly equal to those seen in northern Italy (Venice). The city lies on the boundary between Zone 6 and Zone 7 in terms of the hardiness zone. Architecture Budapest has architecturally noteworthy buildings in a wide range of styles and from distinct time periods, from the ancient times as Roman City of Aquincum in Óbuda (District III), which dates to around 89 AD, to the most modern Palace of Arts, the contemporary arts museum and concert hall. Most buildings in Budapest are relatively low: in the early 2010s there were around 100 buildings higher than . The number of high-rise buildings is kept low by building legislation, which is aimed at preserving the historic cityscape and to meet the requirements of the World Heritage Site. Strong rules apply to the planning, authorisation and construction of high-rise buildings and consequently much of the inner city does not have any. Some planners would like see an easing of the rules for the construction of skyscrapers, and the possibility of building skyscrapers outside the city's historic core has been raised. In the chronological order of architectural styles Budapest is represented on the entire timeline, starting with the Roman City of Aquincum representing ancient architecture. The next determinative style is the Gothic architecture in Budapest. The few remaining Gothic buildings can be found in the Castle District. Buildings of note are no. 18, 20 and 22 on Országház Street, which date back to the 14th century and No. 31 Úri Street, which has a Gothic façade that dates back to the 15th century. Other buildings with Gothic features are the Inner City Parish Church, built in the 12th century,