This peninsula is about 150 miles long and 60 miles wide, projects into the Irish Sea, and is dominated by the Cambrian Mountains. What is it called?

This large peninsula on the western edge of Great Britain fits the description perfectly. It is bordered by the Irish Sea to the north and west, and the Bristol Channel to the south. The rugged Cambrian Mountains form a mountainous spine through its center, and its dimensions are indeed roughly 150 miles from north to south and 60 miles across at its widest point. The country's highest peak, Snowdon (Yr Wyddfa), is located in the northern part of this range.

But this land is much more than just its physical geography. It is one of the four countries that make up the United Kingdom, possessing a distinct cultural identity rooted in its ancient Celtic heritage. The Welsh language, Cymraeg, is one of the oldest in Europe and is still spoken by hundreds of thousands of people, appearing on road signs and in daily life. Known for its dramatic coastlines, mythical folklore, and an abundance of castles, it's a nation where history and nature are deeply intertwined.