How many days should I spend in Lisbon, Portugal, to truly immerse myself in its rich culture and myriad attractions? Is a weekend sufficient, or would it be prudent to allocate a full week to explore its historic neighborhoods and stunning vistas? When considering the time required, should one prioritize iconic landmarks such as the Belém Tower and the Jerónimos Monastery, or is it equally vital to seek out hidden gems nestled within the cobblestone streets of Alfama? Moreover, how will I balance my itinerary between indulging in delectable culinary experiences—perhaps savoring a pastel de nata—and taking leisurely strolls along the scenic Tagus River? As I ponder this question, what would be essential experiences to include? Would it be wise to consider day trips to nearby locales such as Sintra or Cascais? Ultimately, how can I optimize my time to ensure a memorable adventure in this enchanting city? Is it feasible, or should I extend my stay?