100 Front Street (formerly Mechanics National Bank Tower) is a high-rise building located in downtown Worcester, Massachusetts. It is the third tallest building in Worcester (behind Sky Mark Tower and Worcester Plaza, both 288 feet (88 m) high), rising 226 feet (69 m). It was completed in 1971, as a part of the Worcester Center urban renewal project, and has 280,000 square feet (26,000 m²) of interior space. The building is not perfectly square, but rather rectangular, with the short sides being 5 windows across, and the long sides being 7 windows across. The short sides each feature an "M" at the top of the façade above the top floor, because of the original name of the building.