Question: What was the founding year of the incorporated United States City locality in Massachusetts with the most people per square mile ?

text: List of United States cities by population density
Distributions -- States and territories
This section needs to be updated . Please update this article to reflect recent events or newly available information . ( July 2019 ) The following ranks the 50 U.S. states , the District of Columbia , and the 5 inhabited U.S. territories by the number of incorporated places with densities over 10,000 people within them . The `` 10,000+ places '' column only includes incorporated places , it does not include census-designated places ( CDPs ) . If two or more states have the same number of places , as is the case of the 36 states that contain no incorporated places with a density over 10,000 , the states are ranked by the densest incorporated place within the state . The density figures for the densest incorporated place within each state and territory are from the 2010 United States Census , and all the data for this ranking is from the U.S. Census Bureau . [ 3 ] [ 4 ] The first rank column ranks each state by the number of 10,000+ places in that state ( New Jersey ranks first , California ranks second , etc . ) The second rank column ranks the most densely populated place in each state or territory ( Guttenberg , NJ ranks first , Kaser , NY ranks second , etc . ) Hawaii officially does not contain any incorporated places , as the city of Honolulu is coextensive with Honolulu County , which makes up the whole island of Oahu . When the U.S. Census Bureau ranks incorporated places by population , it usually includes the Honolulu census-designated place , which is the urban center of Honolulu , in its ranking of incorporated places . [ 13 ] Therefore , for this list of the densest incorporated places by state , the Honolulu CDP is considered the densest incorporated place in Hawaii . The District of Columbia , Puerto Rico and the U.S. territories are also included in this list . Puerto Rico also officially does not contain any incorporated places , as the lowest form of local government in Puerto Rico are the municipios , which are equivalent to counties . For this ranking , the municipios are counted as the incorporated places in Puerto Rico , and the San Juan Municipio is the densest .
The following is a list of incorporated places in the United States with a population density of over 10,000 people per square mile. As defined by the United States Census Bureau, an incorporated place is defined as a place that has a self-governing local government and as such has been incorporated by the state it is in. Each state has different laws defining how a place can be incorporated and so an incorporated place as recognized by the U.S. Census Bureau can designate a variety of places, such as a city, town, village, borough, and township. [a]
 The other type of place defined by the U.S. Census Bureau for statistical purposes are census-designated places. Census-designated places are distinct from incorporated places because they do not have a local government and thus depend on higher government bodies, such as a county, for governance. Census-designated places are defined as being in an unincorporated area. Census-designated places that have a population density of over 10,000 people per square mile are listed in a separate table below. The five boroughs of New York City, and the census-designated places of Puerto Rico and the Northern Mariana Islands that have densities over 10,000, are also listed in separate tables below.
Rank ( number of 10,000+ places ) State , federal district or territory 10,000+ places Densest incorporated place Density ( people per sq . mile ) Rank ( most dense place )
1 New Jersey 33 Guttenberg 56,012.0 1
2 California 33 Maywood 23,887.2 3
3 New York 23 Kaser 27,788.2 2
4 Pennsylvania 13 Millbourne 16,557.1 7
5 Florida 7 North Bay Village 20,267.1 4
6 Massachusetts 7 Somerville 18,868.1 5
7 Illinois 7 Stone Park 15,378.2 9
8 Kentucky 1 Poplar Hills 17,036.0 6
9 Rhode Island 1 Central Falls 15,652.0 8
10 Maryland 1 Mount Rainier 13,038.5 10
11 Texas 1 Mobile City 11,911.3 11
12 District of Columbia 1 Washington 11,367.0 12
13 Oregon 1 Johnson City 11,061.5 13
14 Michigan 1 Hamtramck 10,900.5 14
15 Ohio 1 Lakewood 10,208.5 15
16 Missouri 0 Velda City 9,872.8 16
17 Puerto Rico 0 San Juan 9,084.4 17
18 Idaho 0 Huetter 9,044.4 18
19 Minnesota 0 Landfall 8,996.8 19
20 Connecticut 0 Bridgeport 8,720.9 20