Every year, in the middle of April, thousands of people go to Boston. They go to run the Boston Marathon. This one of the oldest road races in the United states. It began in 1879.
Each year, more runners join the Boston Marathon. They came from every part of the world.
The Boston race is 26.2 miles, or 42 kilometers. The runners go though thirteen towns during the race. It ends in the center of Boston. Crowds of people watch them as they go though the towns. They clap their hands and cheer for them.