Apollos "Paul" Smith (1825–1912) was an American hunting and fishing guide from Vermont who founded the Saint Regis House in the Town of Brighton, New York, in the Adirondack Mountains.

In its day, it was the most fashionable of the many great Adirondack hotels, patronized by American presidents, celebrities, and the power elite of the latter half of the 19th century.

It was popular from the start with the doctors, lawyers and other professional men from eastern cities with whom Smith had developed a relationship as their hunting guide.

When he sold land, it was generally to his wealthy clientele, many of whom built Great Camps on the nearby lakes, using lumber from Smith's mill.

The hotel expanded steadily to 255 guest rooms, and featured a bowling alley, a large casino, several dormitories for guides and other help, and a stable for 60 horses.

In 1906, Smith built an electric railroad line seven miles (11 km) south to Lake Clear, to connect with the Mohawk and Malone Railway.

Together Smith and Louis Marshall were prominent supporters in gaining the "Forever Wild" Amendment to the New York State Constitution, to preserve Adirondack Park.