① Presumed site of “Spring Wind Pond” at Yokuon-en: Remains believed to be retaining walls discovered during a preliminary survey. Numerous other traces of retaining walls were also found (cited from the Bureau of Urban Development’s website). ② Presumed site of “Autumn Wind Pond” at Yokuon-en: Here, too, numerous stone structures believed to be retaining walls were discovered.Furthermore, traces believed to be fossilized tree remains have also been unearthed.