Although Turner had produced paintings of Italian subjects earlier in his career, it wasn't until 1819, when he was forty-four, that he finally toured the country himself. Having prepared thoroughly for this important journey beforehand, he spent
a rigorous few months sketching and painting in Turin, Milan, Venice and Ancona, before arriving in Rome.
Here, Turner has used a very free,
wet-on-wet watercolour technique
in broad bands of pure colour. The foreground effect may have been achieved with the addition of gum arabic, to slow down the drying of the paint and allow him to drive it around on the paper.