A ride or attraction
Many European cities, such as London and Paris, have a city Ferris wheel that offers expansive views of the city. One reader suggested that Boston do the same. Alan Kawalder from Framingham says that a Ferris wheel would provide "instant tourist attraction and identification for the city" and be a "revenue generator" without concealing a lot of open space. Other readers suggested a carousel.
Pictured here: the EDF Energy London Eye