Along Elliott Way near the Yacht Club, red bricks scatter among the shoreline rocks—remnants of the William A. Underhill Brickyard that operated on Croton Point's northern end. These "Croton Point bricks" carried maker's marks; some featured Underhill's initials (WAU), while others bore the stamp "IXL," a marketing claim meaning "I excel" at brickmaking.

During the 1850s brickmaking boom, over 25 brickyards lined Haverstraw Bay's shores. Within Croton specifically, five yards operated between the area now known as Half Moon Bay and Croton Landing Park's terminus.

The article references a related post titled "History Underfoot" for additional examples of WAU-marked bricks, and cites an 1854 United States Coast Survey document as its source material.