paragraph_text: The National Orchid Garden, located within the Singapore Botanic Gardens, was opened on 20 October 1995 by Singapore's Minister Mentor Lee Kuan Yew.

paragraph_text: Dallam Tower is a grade I listed country house in Beetham parish, near Milnthorpe, South Lakeland, Cumbria, England. It is a member of the Historic Houses Association but is not open to the public except for occasional charity events, visits to the garden through the National Gardens Scheme, and as a wedding venue.

paragraph_text: The Ballarat Botanical Gardens Reserve, located on the western shore of picturesque Lake Wendouree, in Ballarat, Victoria, Australia, covers an area of 40 hectares which is divided into three distinct zones. The central Botanical Gardens reserve in the 'gardenesque' style of the Victorian pleasure garden. On either side there are open parkland buffers known as the North and South Gardens. The Gardens celebrated its sesquicentenary (150 years old) in 2007.

paragraph_text: Another important library – the University Library, founded in 1816, is home to over two million items. The building was designed by architects Marek Budzyński and Zbigniew Badowski and opened on 15 December 1999. It is surrounded by green. The University Library garden, designed by Irena Bajerska, was opened on 12 June 2002. It is one of the largest and most beautiful roof gardens in Europe with an area of more than 10,000 m2 (107,639.10 sq ft), and plants covering 5,111 m2 (55,014.35 sq ft). As the university garden it is open to the public every day.

paragraph_text: Way Four is a public art work by artist Bernard Kirschenbaum at the Lynden Sculpture Garden near Milwaukee, Wisconsin. The stainless steel sculpture is an open circle that creates an orbit for two triangles; it is installed on the lawn.

paragraph_text: The Cleveland Botanical Garden, located in the University Circle neighborhood of Cleveland, Ohio, in the United States, was founded in 1930 as the Garden Center of Greater Cleveland. It was the first such organization in an American city. Originally housed in a converted boathouse on Wade Park Lagoon, the center served as a horticultural library, offering classes and workshops for gardeners and spearheading beautification projects in the community. In 1966, having outgrown its original home, the Garden Center moved to its present location in University Circle, the site of the old Cleveland Zoo. Remnants of the old bear pit still remain in the Ohio Woodland Garden. In 1994, the organization's Board of Trustees changed the name to Cleveland Botanical Garden to reflect a dramatically expanded mission and launched an ambitious capital campaign to develop a facility that would support the enhanced program agenda. The expanded and renovated building, designed by Graham Gund Architects of Cambridge, Massachusetts, opened to the public in July 2003.

paragraph_text: Highline Botanical Garden is a community botanical garden located at 13735 24th Avenue South, SeaTac, Washington. It is open daily without charge.

paragraph_text: Mehan Garden is an open space in Manila, Philippines. It was established in 1858 by the Spanish colonial authorities as a botanical garden, called the "Jardín Botánico", outside the walled city.

paragraph_text: The Jardin botanique de Sedan is a botanical garden and city park located on Philippoteaux Avenue beside the Place d'Alsace-Lorraine, Sedan, Ardennes, Champagne-Ardenne, France. It is open daily without charge.

paragraph_text: The Georgeson Botanical Garden is located at 117 West Tanana Drive on the University of Alaska Fairbanks campus in Fairbanks, Alaska, United States. The five acre garden hosts a variety of research and educational programs in subarctic horticulture. It is open to the public during daylight hours, May through September, for a fee. It is part of the Alaska Agricultural and Forestry Experiment Station. The garden was named after Charles Christian Georgeson, who was USDA Special Agent in Charge of Alaska Investigations in 1899. Dr. Georgeson arrived in Alaska during the Gold Rush to research the possibilities for agriculture in Alaska. He surveyed the land near Fairbanks and started the Fairbanks Experiment Farm. A portion of the land was later annexed for use as the first campus of the University of Alaska.

paragraph_text: Elven C. Smith House is a historic home located at Williamson, Mingo County, West Virginia. It was built in 1938, in a Neo-Classical Revival / Georgian Revival style. It is a red brick building with a hipped roof and features a two-story, flat roofed portico supported by fluted columns. Also on the property is a stone retaining wall and monumental stairway in the landscaped gardens.

paragraph_text: Presby Memorial Iris Gardens is a nonprofit, volunteer-run living museum specializing in iris flowers, located at 474 Upper Mountain Avenue, Montclair in Essex County, New Jersey, New Jersey, United States. The gardens are situated on 6.5 acres. Adjacent to the gardens is a Victorian house, the Walther House. The house is open to the public and is home to a museum shop and headquarters for the Citizens Committee that oversees the gardens.

paragraph_text: Bircher was born at Kensington, London. He was educated at Radley College and Christ's College, Cambridge and in 1948, he was a member of the victorious Cambridge crew in the Boat Race. Most of the Cambridge crew of 1948 also rowed for Leander Club at Henley Royal Regatta. The Leander eight were selected to row for Great Britain in the 1948 Summer Olympics and won the silver medal. Bircher was in the winning Cambridge crews in the 1949 and 1950 Boat Races. In 1953 he was a member of the Leander Club crew which won the Grand Challenge Cup at Henley Royal Regatta.

paragraph_text: Hercules in the Garden of the Hesperides is a 1638 painting by Peter Paul Rubens. It measures 246 cm by 168.5 cm and is now in the Sabauda Gallery in Turin. It shows Hercules in the Garden of the Hesperides and forms part of a pair with the same artist's "Deianira Listens to Fame".

paragraph_text: Boone's Chapel is a Grade I listed, single-storey building attributed to Sir Christopher Wren and built in 1683. The chapel is very small, measuring just 45 square metres and is constructed of red brickwork with Portland stone details to window architraves, rusticated quoins and a pyramidal roof with an open wood cupola. It is located adjacent to the Worshipful Company of Merchant Taylors almshouses on Lee High Road in Lewisham, London and is one of only two Grade I-listed buildings in the borough of Lewisham (the other is St Paul's, Deptford).

paragraph_text: The building housed the department store Derry and Toms until 1973, and then Biba until 1975. Since the 1980s the garden has been used as a restaurant and club.

paragraph_text: Jimmy McNeece was a professional American Lightweight boxer from Oakdale, Long Island, New York. As an amateur boxer, McNeece won the 1976 New York Golden Gloves 112 lb. Open Championship. McNeece defeated amateur standout and future professional boxing star Paul Devorce in the finals at Madison Square Garden.

paragraph_text: Garden of Prayer is a 1954 album of songs recorded by American singer Jo Stafford, accompanied by the orchestra of Paul Weston. Each of the eight tracks on this album has a religious or inspirational theme. It was released in 1954 by Columbia Records (CL 6286), then reissued on CD in 2010 by Sinetone AMR, and appears under two titles - either Garden of Prayer or Beautiful Garden of Prayer.

paragraph_text: Garvan Woodland Gardens is a 210-acre (850,000 m²) botanical garden located at 550 Arkridge Road, approximately 6 miles from Hot Springs National Park in Hot Springs, Arkansas, United States. Owned by the University of Arkansas, it has the stated mission of education, research and public service. For an admission fee, it is open daily, except on Thanksgiving Day, Christmas Day and the month of January.

paragraph_text: In 2006, the Yankees began building a new $2.3 billion stadium in public parkland adjacent to the stadium. The price included $1.2 billion in public subsidies. The design includes a replica of the frieze along the roof that was in Yankee Stadium. Monument Park, a Hall of Fame for prominent former Yankees, was relocated to the new stadium. Yankee Stadium closed following the 2008 baseball season and the new stadium opened in 2009, adopting the ``Yankee Stadium ''moniker. The original Yankee Stadium was demolished in 2010, two years after it closed, and the 8 - acre site was converted into a park called Heritage Field. The new Yankee stadium opened in 2009 and is currently used by the NY Yankees.

Question: When did the roof gardens above Paul Bircher's birthplace open to the public?
Answer: 1980s