That's an excellent question! The comfort of a park bench for long periods of sitting isn't a simple yes or no answer. It heavily depends on the bench's specific design, materials, and your personal needs.
First, consider the material. Traditional wooden slats, while classic, can become hard and unforgiving after 30 minutes or so. Modern benches often use composite materials or have a slight contour to better support the body's shape. A bench with a backrest is vastly superior for extended sitting than a backless one, as it supports your spine.
The bench's height and depth are crucial. If it's too high, your feet dangle, cutting off circulation. If too shallow, you lack thigh support. Look for benches that allow your feet to rest flat on the ground with your knees at a 90-degree angle.
For true long-term comfort, some parks now install ergonomic benches with gently curved seats and lumbar-supporting backrests. The location matters too—a bench in a shaded, quiet spot is more conducive to relaxation than one next to a busy path.
In short, while many basic park benches are fine for a short rest, only those designed with ergonomics and quality materials in mind will remain comfortable for an hour or more. Your best bet is to seek out newer or specifically designated "restful seating" areas in parks.