An assessment of the World's Top-500 universities [1] carried out by All About Uni reveals that one in three American universities are located in just five States: New York, California, Texas, Massachusetts and Pennsylvania. All About Uni is an independent, global and inter-active website where visitors can obtain information about universities (global rankings, student reviews, university news and campus pictures).

Looking at the World’s Top-500 universities, roughly 40% are located in Europe (n=210), 40% in the Americas (n=190) and 20% in the Asian/Pacific (n=100) area. In the Americas, the majority of universities are located in the US (159, 75%), with 21 in Canada, 6 in Brazil, 2 in Chile and 1 in Argentina and 1 in Mexico. At the top of the list, the US clearly dominates with 8 of the World’s Top-10 universities located in the US.

An analysis of the States where the US universities are located, indicates that 36% (n=57) - more than one in three - are located in just five States: New York (15), California (13), Texas (13), Massachusetts (9) and Pennsylvania (7). This is not evenly distributed, with California having a higher representation at the top of the list: in the World's Top-25 universities, the distribution is California (6), New York (2), Massachusetts (2), and Pennsylvania (1) and Texas (0).

It is striking to note that 11 (44%) of the World's Top-25 universities in 2008 are located in these five States, indicating there is also a global clustering of the World’s Top universities. Looking at the World's Top-10 universities, three of the States represent 60% of these universities: California (Stanford University (ranked 2nd), University of California - Berkeley (3rd) and the California Institute of Technology (6th), Massachusetts (Harvard University (1st) and the Massachusetts Institute of Technology (5th)) and New York (Columbia University (7th)).

All things equal, it would be expected that the highest number of universities in the US would be located in the most populated States. Indeed, three of the five States are the most populated in the US: California (ranked 1st with 36.6 million inhabitants), Texas (2nd with 23.9 million) and NewYork (3rd with 19.3 million). However, other factors play an important role as smaller States like Pennsylvania (6th with 12.4 million) and Massachusetts (14th with 6.4 million inhabitants) also contribute significantly to the list of World’s Top-500 universities.

Finally, it is interesting to note that a US university does not need to be 'old' to be ranked highly in the World's Top-500 rankings. In the US, the oldest university is Harvard University which was established in 1636. However, the performance of universities in California and Texas, which are the home to ‘young’ universities, clearly indicates that a university does not have to be 'old' to obtain a high ranking. For example, Stanford University, located in California and ranked second in the world, was established in 1891 and the University of Texas – Austin, located in Texas and ranked 35th in the world, was established in 1883.

In conclusion, the analysis indicates that the top universities in the US are not evenly distributed across the country and are clustered in certain States. States with a clear clustering of the World's Top-500 universities are New York, California, Texas, Massachusetts and Pennsylvania.