Approximately 700. For the exact figure contact the Service department of the Britain Branch of Jehovah's Witnesses (see link below)
As of July 2015, there are 7 Kingdom Halls with about 30 congregations. Their website has a Kingdom Hall finder that you can use to find the closest to you and that speaks your language.
According to the 2010 Annual Report of Jehovah's Witnesses there were 107,210 congregations worldwide. The number of Kingdom Halls in which they meet is not recorded (that I can find) but would be lower than this figure as many congregations share Kingdom Halls and others may rent buildings to meet in.
Many Kingdom Halls in New York offer temple child care. Call and inquire from phone (718) 389-4726
Most Kingdom Halls are multicultural and carry multi-lingual literature, however there are various foreign language congregations in many cities throughout the United States.
This is a misunderstanding that many people have. There are some kingdom halls that are built with windows. However, it is primarily a cost savings to have no windows and it reduces opportunities for vandalism.
There are 9 Kingdom Halls of Jehovah's Witnesses in Winnipeg proper. But each of the 9 Kingdom Halls have at least 2, or 3 congregations meeting in them. Other religions will need to pipe-in for more information on their own religions.
There are dozens of Kingdom halls in Maryland USA. The service department at the Headquarters of Jehovah's Witnesses has the exact figure; you can contact them by writing to: 25 Columbia Heights, Brooklyn, NY 11201-2483.
Look at jw.org
Kingdom Halls
Is there a Kingdom Hall of Jehovah' Witnesses in Jaco Costa Rica
Jehovah's Witnesses do not have kingdom ministry halls. We have Kingdom Halls. We also have Kingdom Ministry Schools; and Theocratic Ministry Schools. Theocratic Ministry Schools are held each week in all Kingdom Halls. Kingdom Ministry Schools are only for elders; held very rarely. Dates and places are not made available to the rank & file Witness. It's by personal invitation only.
Yes there are Kingdom Halls of Jehovah's Witnesses in the Holy Land. According to the 2010 annual report, as published by Jehovah's Witnesses, there are 21 congregations in the state of Israel. The number of Kingdom Halls are not publicly published.