We will be driving from Lisbon to Porto and wanted to stop and experience things along the way. I've heard great things about both Coimbra and Obidos, but we can only choose one due to time constraints. Coimbra seems rich in history and university culture, while Obidos charms with its medieval walls and quaint streets. Has anyone visited both? Which would you recommend for a more memorable stop, especially for someone who loves history and picturesque settings?