May Pen serves as the capital and largest town within the parish of Clarendon in Middlesex County, Jamaica. Situated on the banks of the Rio Minho river, it functions as a major market centre for the surrounding agricultural region. Its central geographical position near the middle of the island makes it a key administrative hub, hosting local government headquarters and a court house.

Originally established as May's Pen, a cattle farm settlement by the British between 1660 and 1683, the town grew around a crossing point on the Rio Minho. It became part of an estate owned by Reverend William May, a slave trader who oversaw twenty-seven enslaved people. The area developed significantly with the arrival of the railway in the late nineteenth century, which transformed it into a vital crossroads for natural resources.

The town centre is characterized by a chaotic mix of shoppers, vendors, and motorized traffic along Main Street and Sevens Road. A prominent clock tower erected in 1908 commemorates Dr. Robert Glaister Samuel Bell and World War I veterans. Three bridges cross the river, including a steel railway bridge opened in 1925 and later used for road traffic until the railway ceased operations in 1992.

May Pen is an important citrus packing centre for oranges and ugli fruit, with the Denbigh Agricultural Showground located nearby. This showground, the largest in the English-speaking Caribbean, hosts an annual event during Jamaica's Independence Celebration weekend, attracting crowds to view agricultural output and livestock. The town also features numerous banks, hardware stores, pharmacies, and eateries that support its commercial character.

The population was 61,548 at the 2011 census, having increased from 59,550 in 2001. The economy relies heavily on agriculture, citrus production, and the Alcoa mining refinery, which is the single largest employer. Transport access includes the T1 Highway route developed in 2012 and a bypass built in 1982, while education is provided by several public and private high schools.