You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Neolithic

Context:
Neolithic peoples in the Levant, Anatolia, Syria, northern Mesopotamia and Central Asia were also accomplished builders, utilizing mud-brick to construct houses and villages. At Çatal höyük, houses were plastered and painted with elaborate scenes of humans and animals. In Europe, long houses built from wattle and daub were constructed. Elaborate tombs were built for the dead. These tombs are particularly numerous in Ireland, where there are many thousand still in existence. Neolithic people in the British Isles built long barrows and chamber tombs for their dead and causewayed camps, henges, flint mines and cursus monuments. It was also important to figure out ways of preserving food for future months, such as fashioning relatively airtight containers, and using substances like salt as preservatives.

Question:
Where do thousands of early tombs still exist?

Ireland