Built of Manhattan mica-schist with brownstone quoins, St. Paul's has the classical portico, boxy proportions and domestic details that are characteristic of Georgian churches including James Gibbs' St Martin-in-the-Fields in London.

Inside, the chapel's hall has pale colors, flat ceiling and cut glass chandeliers reminiscent of contemporary domestic interiors.

Recent documentation published by historian John Fitzhugh Millar suggests architect Peter Harrison may have instead been responsible for the structure's design.

It stood in a field some distance from the growing port city to the south and was built as a "chapel-of-ease" for parishioners who found the mother church inconvenient to access.

[8] Below the east window is the monument to Brigadier General Richard Montgomery, who died at the Battle of Quebec (1775) during the American Revolutionary War.

The Hearts of Oak, a militia unit organized early in the American Revolutionary War, and composed in part of King's College (later, Columbia University) students, would drill in the chapel's yard before classes nearby.

After the attacks on September 11, 2001, which led to the collapse of the twin towers of the World Trade Center, St. Paul's Chapel served as a place of rest and refuge for recovery workers at the WTC site.

For nine months, hundreds of volunteers worked 12-hour shifts around the clock, serving meals, making beds, counseling and praying with fire fighters, construction workers, police and others.

After it became filled with flowers, photos, teddy bears, and other paraphernalia, Trinity officials decided to erect a number of panels on which visitors could add to the memorial.

The first one when entering is "Healing Hearts and Minds", which consists of a policeman's uniform covered with police and firefighter patches sent from all over the U.S., including Iowa, West Virginia, and California.

The churchyard has long been a pastoral oasis in busy lower Manhattan, but decades of damage and the sharp rise in tourism necessitated a revitalization.

The sensitive site, which includes human remains, fragile stone grave markers, and mature tree roots, was treated at the surface level, with all work done by hand.

[10][14][15] St. Paul's Chapel is an active part of the Parish of Trinity Church, holding services, weekday concerts, and occasional lectures.