text: There are two buildings. The grey area on openstreetmap is in fact bigger. So on the left where the red circle is, there is also this big buildings. One huge office complex completely New and a second one, also maybe 8 floors up ...but in this little bit smaller building there is the ice rink as you Showed in your link. It is the Trainings facility of the Boston bruins NHL Hockey Franchise! The rink has opened a few Weeks ago. You can See the buildings in Google steetview!some parts are still under construction.
  
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