The Web has become closely ingrained with our life and work and massive effort for Web development and maintenance continue to take place in an ad hoc manner, resulting in poor quality Web systems and applications. As a consequence, web engineering and more precisely web requirements engineering is becoming of major importance in web development process. In this paper, we will tackle the validation phase of web requirements engineering; whereby we present a new navigational requirements' validation approach that verifies the completeness, correctness, and consistency of the web navigations. A navigational model has been added to the different models of the development lifecycles; it represents the navigational requirements of the application and is considered as part of the behavioral model. All in all, we propose a web-based navigational requirements validation through visualization and animation.