diff --git a/handMadeCalendarAdvance/NewCalendarViewController.swift b/handMadeCalendarAdvance/NewCalendarViewController.swift
index 11b8ab3..11845cc 100644
--- a/handMadeCalendarAdvance/NewCalendarViewController.swift
+++ b/handMadeCalendarAdvance/NewCalendarViewController.swift
@@ -14,6 +14,21 @@ class NewCalendarViewController: UIViewController {
     // 日本の祝祭日判定用のインスタンス
     private let holidayObject: CalculateCalendarLogic = CalculateCalendarLogic()
 
+    private var stringDateFormatter: DateFormatter = {
+        let dateFormatter = DateFormatter()
+        dateFormatter.locale = Locale(identifier: "ja_JP")
+        dateFormatter.timeZone = TimeZone.current
+        dateFormatter.dateFormat = "yyyy/MM/dd"
+        return dateFormatter
+    }()
+
+    private var currentCalendar: Calendar = {
+        var calendar = Calendar.current
+        calendar.locale = Locale(identifier: "ja_JP")
+        calendar.timeZone = TimeZone.current
+        return calendar
+    }()
+
     override func viewDidLoad() {
         super.viewDidLoad()
         setupCalendarView()
@@ -25,9 +40,13 @@ class NewCalendarViewController: UIViewController {
         if #available(iOS 16.0, *) {
             let calendarView = UICalendarView()
             calendarView.calendar = Calendar(identifier: .gregorian)
-            calendarView.locale = Locale(identifier: "ja")
+            calendarView.locale = Locale(identifier: "ja_JP")
             calendarView.delegate = self
-
+            // 例. 任意の日付を1つ選択可能にする
+            // 補足: 複数日付を選択する場合はこちらをする
+            // https://developer.apple.com/documentation/uikit/uicalendarselectionmultidate
+            let dateSelection = UICalendarSelectionSingleDate(delegate: self)
+            calendarView.selectionBehavior = dateSelection
             view.addSubview(calendarView)
             calendarView.translatesAutoresizingMaskIntoConstraints = false
             calendarView.topAnchor.constraint(equalTo: self.view.safeAreaLayoutGuide.topAnchor).isActive = true
@@ -64,14 +83,59 @@ extension NewCalendarViewController: UICalendarViewDelegate {
     @available(iOS 16.0, *)
     func calendarView(_ calendarView: UICalendarView, decorationFor dateComponents: DateComponents) -> UICalendarView.Decoration? {
         guard let targetYear = dateComponents.year,
-            let targetMonth = dateComponents.month,
-            let targetDay = dateComponents.day else {
+              let targetMonth = dateComponents.month,
+              let targetDay = dateComponents.day else {
             return nil
         }
-        if holidayObject.judgeJapaneseHoliday(year: targetYear, month: targetMonth, day: targetDay) {
+
+        // 注意: weekdayプロパティはUICalendarViewDelegateまで常にnilになる...
+        // print("dateComponents.weekday", dateComponents.weekday)
+
+        let weekday = getWeekDay(year: targetYear, month: targetMonth, day: targetDay)
+        let isHoliday = holidayObject.judgeJapaneseHoliday(year: targetYear, month: targetMonth, day: targetDay)
+
+        if isHoliday {
             return .image(UIImage(systemName: "flag.2.crossed.fill"), color: .orange, size: .medium)
+        } else if weekday == 1 {
+            return .default(color: .red, size: .small)
+        } else if weekday == 7 {
+            return .default(color: .blue, size: .small)
         } else {
             return nil
         }
     }
+
+    // 年・月・日から曜日（日曜日:1 ~ 土曜日:7）を取得する
+    private func getWeekDay(year: Int, month: Int, day: Int) -> Int {
+        let formatString = "%04d/%02d/%02d"
+        guard let date: Date = stringDateFormatter.date(from: String(format: formatString, year, month, day)) else {
+            return 0
+        }
+        return currentCalendar.component(.weekday, from: date)
+    }
+}
+
+// MARK: - UICalendarSelectionSingleDateDelegate
+
+extension NewCalendarViewController: UICalendarSelectionSingleDateDelegate {
+
+    // 日付を選択したタイミングで選択した日付情報を返す
+    @available(iOS 16.0, *)
+    func dateSelection(_ selection: UICalendarSelectionSingleDate, didSelectDate dateComponents: DateComponents?) {
+        guard let targetDateComponents = dateComponents else {
+            return
+        }
+        guard let targetYear = targetDateComponents.year,
+            let targetMonth = targetDateComponents.month,
+            let targetDay = targetDateComponents.day else {
+            return
+        }
+        print("あなたが選択した日付:", "\(targetYear)年\(targetMonth)月\(targetDay)日")
+    }
+
+    // 日付を選択可能な状態とするかを設定する
+    @available(iOS 16.0, *)
+    func dateSelection(_ selection: UICalendarSelectionSingleDate, canSelectDate dateComponents: DateComponents?) -> Bool {
+        return true
+    }
 }