Bostons North End is known for its Italian heritage and its narrow streets and brick buildings. It is the oldest neighborhood in the city, having been continuously inhabited since it was first settled in the 1630s. The North End takes its name from being located at the northern most tip of the Shawmut Peninsula and it was originally much smaller than it is today. As with many of the neighborhoods in Boston, with land at a premium waterways were filled in order to create more habitable space. Along the waterfront of the North End, commercial areas were increased with fill removed from Beacon Hill which at the time was being developed for residential uses. Many of the first residents of the North End were merchants and traders who purchased land close to the water and built houses, warehouses and wharves. As their wealth increased, many of the merchants built large homes in the area as the North End became a very fashionable place to live in the 18th century. After the American Revolution however, many of the wealthier members of society were drawn away from the waterfront and many of the large houses were either turned into multi-unit dwellings or torn down and replaced by row houses. As immigration increased in the 19th century, the North End became a haven for immigrants, and by 1855 almost half of the residents of the North End were Irish. Over the next 20 years as the Irish moved on, more and more Polish and Russian immigrants settled in the area. Then, in the late 1870s Italian immigration began, and by the 1920s an estimated 90% of the residents were Italian. Much of the Italian heritage of the neighborhood remains today, with the numerous Italian street festivals and the restaurants and bakeries being among the citys best. Over the last several years access to the area was difficult and the North End struggled through some of the major construction projects that have recently been completed. Now, the steel beams and girders that held up the Central Artery and separated the North End from the rest of downtown have been removed and replaced with green space known as the Rose Kennedy Greenway. Significant landmarks include Paul Reveres house, the Old North Church and Hanover Street.