The United States Congress is the legislative branch of government, which makes laws and passes bills. Congress is made up of two parts -- the House of Representatives and the Senate. Even though Congress is the lawmaking branch of government, it has rules it has to follow too. These rules are spelled out in the U.S. Constitution. One of these rules is that Congress must meet at least once per year.

The First Meeting

The first Congress that met after the Constitution was in effect convened March 4, 1789. Article 1, Section 4 of the Constitution set the original meeting on the first Monday in December, unless Congress passed a law to meet at another time, which it did on many occasions. In 1933, the 10th Amendment to the Constitution changed the meeting date to January 3, unless Congress passes a law to change the date.

When Does Congress Meet?

For many years, Congress would meet in December and be done by May. At the time, travel was limited to carriages, horses and ships. Getting to the meeting was not an easy task. When the start of the session moved from December to January, sessions lasted into the summer months. When planes made the trip hours rather than days or weeks, Congress began meeting year-round, with members going home on weekends and holidays. Many members of Congress consider the time at home work as well, since they talk with people from their state while they are there.

Where Does Congress Meet?

The first few sessions of Congress were held in New York City, then in Philadelphia. After the first session of the Sixth Congress, the meeting moved to Washington, D.C., where it has taken place ever since. Originally, the whole of the United States was along the East Coast, making the meeting only a few days' journey from each state. As the country expanded, the length of the journey increased for many representatives.

How Long Is a Session?

The Congressional calendar is set each year. In 2013, for example, the House of Representatives have 126 scheduled meeting days, while the Senate is scheduled to meet approximately three weeks out of each month. The off-weeks are generally scheduled around holidays. Both houses have the month of August off and meet each week in June. Days may be half-days or full days to count as a day in session, and weeks may be three, four or more rarely five days long.