This little script provides you a way to have pretty URLs in your php web site. If you just want to have routes but you do not want to bother with massive php frameworks, you could find this useful
Routing and filtering extension system for yii2 framework that emulates the laravel routing system
Laravel Router Standalone
An organized approach to handling routes in Laravel.
This repo is the code used in the DevDojo Creating a PHP Routing System Video Series
A testable route system with localization for Laravel 5 to 7
A Laravel integration with Swagger UI.
Integrates static laravel-like routes and filtering into codeigniter 3.x and 2.x