Question: What is the longest street of the suburb that borders Enfield at the Northern end?
Context: Barton Street is an arterial road in the Lower City of Hamilton, Ontario, Canada.  It's also the longest street (21.0 km) in the city.  It starts off at the Western end of town at Locke Street North and is a two-way street that stretches eastward through a number of different and varied communities in the city and ends in Winona at "Fifty Road" just West of the Hamilton/Niagara regional border. Nelson Mandela Boulevard (Persian: بلوار نلسون ماندلا‎ ‎ ) (old name: Jordan Street and Africa Boulevard) still known as Jordan is an affluent and upper-class district in northern Tehran, where a lot of people consider Jordan District as being very similar to Kensington District in London, UK as the area is a residential and commercial locale and is filled with the homes and businesses of many politicians, diplomats, expatriates, and artists.  Before Iranian Revolution in 1979 it was named Jordan and used to be the most popular avenue in Tehran, Iran.  Nelson Mandela Boulevard is the most famous street in Tehran after Valiasr Street which is the longest street in the Middle East, spanning a south-north axis.  It is also famous for being one of the liveliest streets of Tehran, experiencing regular traffic jams even at 2:00A.M during Summer. Enfield is a suburb in Adelaide, Australia.  The suburb is about a 10-minute drive north from Adelaide's Central Business District.  The suburb is bordered by Gepps Cross, Blair Athol and Clearview at the Northern end, and Prospect, Sefton Park and Broadview at the Southern end. Duke Street is a street in Glasgow, Scotland, often stated to be the longest street in Britain but King Street, Aberdeen is 0.2 mi longer.  Duke Street runs from the city centre to the East End, from High Street through the residential district of Dennistoun, past The Forge Shopping Centre, meeting the Gallowgate, Tollcross Road and Westmuir Street to form a turreted Edwardian junction at Parkhead Cross. Washington Street is a street originating in downtown Boston, Massachusetts that extends southwestward to the Massachusetts–Rhode Island state line.  The majority of it was built as the Norfolk and Bristol Turnpike in the early 19th century.  It is the longest street in Boston, and it remains one of the longest streets in the state of Massachusetts. Gdańska Street is one of the main street of downtown Bydgoszcz, Poland.  Initially, the street was a thoroughfare, but in the second half of the 19th century, it turned residential.  It ran from the Brda river to Bydgoszcz northern part of town an has gradually become the city center of trade and entertainment.  During the interwar period, Gdańska street was the third longest street in Bydgoszcz with a total length of 3.19 km. Yonge Street ( ; "young") is a major arterial route connecting the shores of Lake Ontario in Toronto to Lake Simcoe, a gateway to the Upper Great Lakes.  Until 1999, the "Guinness Book of World Records" repeated the popular misconception it was 1896 km long, and thus the longest street in the world; this was due to a conflation of Yonge Street with the rest of Ontario's Highway 11.  Yonge Street (including the Bradford-to-Barrie extension) is actually 86 kilometres long.  The construction of Yonge Street is designated an Event of National Historic Significance in Canada.  Yonge Street was fundamental in the original planning and settlement of western Upper Canada in the 1790s, informing the basis of the concession roads in Ontario today.  Once the southernmost leg of Highway 11, linking the capital with northern Ontario, Yonge Street has been referred to as "Main Street Ontario".  Today, no section of Yonge Street is a provincial highway. Blair Athol is located about 15 km north of the Adelaide CBD, South Australia.  Blair Athol borders the suburbs of Gepps Cross, Enfield, Prospect and Kilburn.  Blair Athol's main and longest street is Florence Avenue. Ilica street is one of the longest streets in Zagreb, Croatia.  The busy street is home to many shops and cultural sites and spans through most of the northwestern part of the city, from the Ban Jelačić Square in the city centre westward to the Vrapče district.  The street is 5.66 km long, making it the third longest street in the city. Valiasr Street (Persian: خیابان ولی‌عصر‎ ‎ ) is a tree-lined street in Tehran, Iran, dividing the metropolis into western and eastern parts built in 1922 to 1927, considering the end of asphalt plan it ended in 1933.  It is considered one of Tehran's main thoroughfares and commercial centres.  It is also the longest street in the Middle East, and was reported as one of the longest in the world by former BBC (now Al Jazeera) journalist Rageh Omaar during the television documentary "Welcome to Tehran".
Answer: Florence Avenue