In this paper, we investigate how the Semantic Web can enhance web navigation and accessibility by following a hybrid approach of document-oriented and data-oriented considerations. Precisely, we propose a methodology for specifying, extracting. and presenting semantic data embedded in (X)HTML documents with RDFa in order to enable and improve ubiquitous web navigation and accessibility for end-users. In our context, embedded data does not only contain data type property annotations, but also object properties for interlinking, and embedded domain knowledge for enhanced content navigation through ontology reasoning. We provide a prototype implementation, called Semantic Web Component (SWC) and evaluate our methodology along a concrete scenario for mobile devices and with respect to precision, performance, network traffic, and usability. Evaluation results suggest that our approach decreases network traffic as well as the amount of information presented to a user without requiring significantly more processing time, and that it allows creating a satisfactory navigation experience.