Complex sentence: The ancient Oxford City Wall, belonging to New College, is often noted for when William of Wykeham founded the college, he formally agreed to maintain the city wall when he acquired the land on which to build the college.
Split into simpler sentences: The ancient Oxford City Wall, belonging to New College, is of particular interest. When William of Wykeham founded the College, he formally agreed to maintain the City Wall when he acquired the land on which to build the College.