That's an excellent question about getting truly comfortable outdoors! The direct answer is that most traditional, permanent park benches you encounter have a fixed backrest angle. They are designed for general, upright seating to accommodate a wide range of people and ensure durability against constant public use and weather. Their fixed design is a matter of practicality, cost, and vandal-resistance.
However, the world of public seating is evolving! You can increasingly find innovative benches designed for enhanced relaxation. Some modern styles feature a gently reclined, ergonomic curve built into a fixed frame, offering a more relaxed posture than a standard 90-degree angle. In certain upscale parks, plazas, or private communities, you might even encounter benches with adjustable or movable backrests. These are often more robust, specially engineered models.
For the ultimate relaxed angle, many people seek out classic "recliner" or "contour" style benches. These have a long, sweeping seat and back that form a continuous, sloping curve, perfect for lying back and gazing at the sky. Your best strategy is to explore different parks and note the bench designs. Look for longer, curved benches or those labeled as "loungers." While you typically can't *adjust* a standard bench, you can certainly *select* one designed with a more leisurely angle for your perfect moment of park-side relaxation.