Lucentum is the Roman predecessor to modern Alicante, a well-excavated site on a hill called Tossal de Manises about four kilometres from the city centre. The ruins include streets, forum foundations, house floors with mosaic remnants, and sections of the defensive wall. The site is small enough to explore in an hour and well-labelled in Spanish and English.
The location is striking — the hill rises from a flat plain, and from the top you can see across to the modern city and the sea beyond. The site museum (part of the MARQ system) provides context, though many of the best finds are in the main MARQ building in town. The combination of both sites makes for a worthwhile archaeology day in Alicante.