As it turns out, having fabulously wealthy American magnates for fellow parishioners has a way of ensuring equally fabulous decorations within one’s house of worship.

Located just below the Rockefeller’s Kykuit estate in Westchester County, New York, the Union Church of Pocantico Hills is home to an unexpected artistic treat. Embedded within the church’s steeply pitched gables are gorgeous, little-known works by both early 20th-century luminaries Henri Matisse and Marc Chagall.

A glorious rose window created by Henri Matisse is the artist’s last completed work before his death in 1954. Commissioned by Nelson A. Rockefeller, the window is a memorial for his mother, Abby Aldrich Rockefeller. Bringing even more brilliant light into Union Church are nine windows designed by Chagall, eight of which are interspersed throughout the church’s nave. Most stunning of all is one which has become known as the “Good Samaritan” window, comemmorating Abby Rockefeller’s husband, John Jr., at the behest of their son, David.

While it’s hardly strange that a well-to-do family of cultural connoisseurs like the Rockefellers would commission works of art as gifts and memorials to each other, the wondrous element of the glass pieces at Union Church remains how they’ve continued to remain hidden in plain, public view, even after more than half a century of existence.