diff --git a/TimeKeeping/DotNetThoughts.TimeKeeping.App/Pages/Timer.razor b/TimeKeeping/DotNetThoughts.TimeKeeping.App/Pages/Timer.razor
index b8397d1..21f3c4c 100644
--- a/TimeKeeping/DotNetThoughts.TimeKeeping.App/Pages/Timer.razor
+++ b/TimeKeeping/DotNetThoughts.TimeKeeping.App/Pages/Timer.razor
@@ -2,31 +2,60 @@
 
 <PageTitle>Timing</PageTitle>
 
-<h1>System Time</h1>
-<p role="status">@systemTime.ToString("O")</p>
+<h1>UTC Real Time</h1>
+<p role="status">@realTime.ToString("O")</p>
+<div>
 <button class="btn btn-primary" @onclick="SetBaseLine">Baseline 2021-01-01</button>
 <button class="btn btn-primary" @onclick="FreezeAbsolute">Freeze 2021-01-01</button>
-<button class="btn btn-primary" @onclick="AdvanceOneHour">Advance 1 Hour</button>
-<button class="btn btn-primary" @onclick="SubtractOneHour">Subtract 1 Hour</button>
 <button class="btn btn-primary" @onclick="Freeze">Freeze</button>
 <button class="btn btn-primary" disabled="@IsNotFrozen()" @onclick="Thaw">Thaw</button>
 <button class="btn btn-primary" @onclick="Reset">Reset</button>
-<h1>Real Time</h1>
-<p role="status">@realTime.ToString("O")</p>
+</div>
+<div>
+<button class="btn btn-primary" @onclick="AdvanceOneHour">Advance 1 Hour</button>
+<button class="btn btn-primary" @onclick="AdvanceOneDay">Advance 1 Day</button>
+<button class="btn btn-primary" @onclick="AdvanceOneWeek">Advance 1 Week</button>
+</div>
+<div>
+<button class="btn btn-primary" @onclick="SubtractOneHour">Subtract 1 Hour</button>
+<button class="btn btn-primary" @onclick="SubtractOneDay">Subtract 1 Day</button>
+<button class="btn btn-primary" @onclick="SubtractOneWeek">Subtract 1 Week</button>
+</div>
 
+<h1>UTC System Time</h1>
+<p role="status">@systemTime.ToString("O")</p>
+
+<h1>Local System Time</h1>
+<p role="status">@localSystemTime.ToString("O")</p>
+
+<h1>
+    <select value="@selectedTimeZone" @onchange=OnTimeZoneChange>
+        @foreach (var tz in TimeZoneInfo.GetSystemTimeZones())
+        {
+            <option value="@tz.Id">@tz.Id Local System Time</option>
+        }
+    </select>
+</h1>
+<p role="status">@nairobiLocalSystemTime.ToString("O")</p>
 
 
 @code {
     private int currentCount = 0;
     private TimeTravelersClock clock = new TimeTravelersClock();
-    private DateTimeOffset systemTime = DateTimeOffset.UtcNow;
     private DateTimeOffset realTime = DateTimeOffset.UtcNow;
+    private DateTimeOffset systemTime = DateTimeOffset.UtcNow;
+    private DateTimeOffset localSystemTime = DateTimeOffset.UtcNow;
+    private DateTimeOffset nairobiLocalSystemTime = DateTimeOffset.UtcNow;
+    private string selectedTimeZone = TimeZoneInfo.GetSystemTimeZones().First().Id;
     System.Threading.Timer? timer;
 
     private void UpdateUI()
     {
         systemTime = clock.UtcNow();
         realTime = DateTimeOffset.UtcNow;
+        localSystemTime = new LocalDateTime(systemTime.DateTime, TimeZoneInfo.Utc).ToTimeZone(TimeZoneInfo.Local).ToDateTimeOffsetLocal();
+        nairobiLocalSystemTime = new LocalDateTime(systemTime.DateTime, TimeZoneInfo.Utc).ToTimeZone(TimeZoneInfo.FindSystemTimeZoneById(selectedTimeZone)).ToDateTimeOffsetLocal();
+
     }
     protected override void OnInitialized()
     {
@@ -38,6 +67,11 @@
             await InvokeAsync(StateHasChanged);
         }, null, 0, 10);
     }
+
+    private void OnTimeZoneChange(ChangeEventArgs args)
+    {
+        selectedTimeZone = ((string)args.Value);
+    }
     private void AdvanceOneHour()
     {
         clock.Advance(TimeSpan.FromHours(1));
@@ -45,11 +79,36 @@
 
     }
 
+    private void AdvanceOneDay()
+    {
+        clock.Advance(TimeSpan.FromDays(1));
+        UpdateUI();
+
+    }
+
+    private void AdvanceOneWeek()
+    {
+        clock.Advance(TimeSpan.FromDays(7));
+        UpdateUI();
+
+    }
+
     private void SubtractOneHour()
     {
         clock.Advance(TimeSpan.FromHours(-1));
         UpdateUI();
+    }
+
+    private void SubtractOneDay()
+    {
+        clock.Advance(TimeSpan.FromDays(-1));
+        UpdateUI();
+    }
 
+    private void SubtractOneWeek()
+    {
+        clock.Advance(TimeSpan.FromDays(-7));
+        UpdateUI();
     }
 
     private void Freeze()
diff --git a/TimeKeeping/DotNetThoughts.TimeKeeping.Tests/LocalDateTimeTests.cs b/TimeKeeping/DotNetThoughts.TimeKeeping.Tests/LocalDateTimeTests.cs
index 9cc45b4..22988cb 100644
--- a/TimeKeeping/DotNetThoughts.TimeKeeping.Tests/LocalDateTimeTests.cs
+++ b/TimeKeeping/DotNetThoughts.TimeKeeping.Tests/LocalDateTimeTests.cs
@@ -12,6 +12,51 @@ public void TestLocalDateTimeOffset()
         ldt.ToDateTimeOffsetLocal().Should().Be(expectedDateTimeOffset);
     }
 
+    [Fact]
+    public void ConvertBetweenTimeZones_Utc()
+    {
+        var t = new DateTime(2024, 06, 06, 0, 0, 0, DateTimeKind.Unspecified);
+        var tz = TimeZoneInfo.FindSystemTimeZoneById("Central European Standard Time");
+        var ldt = new LocalDateTime(t, tz);
+        var utc = ldt.ToTimeZone(TimeZoneInfo.Utc);
+        utc.DateTime.Kind.Should().Be(DateTimeKind.Utc);
+        utc.ToDateTimeOffsetUtc().Should().Be(ldt.ToDateTimeOffsetUtc());
+    }
+
+    [Fact]
+    public void UtcIsLocalUtc()
+    {
+        var t = new DateTime(2024, 06, 06, 0, 0, 0, DateTimeKind.Utc);
+        var tz = TimeZoneInfo.FindSystemTimeZoneById("UTC");
+        var ldt = new LocalDateTime(t, tz);
+        ldt.ToDateTimeOffsetLocal().Should().Be(ldt.ToDateTimeOffsetUtc());
+    }
+
+    [Fact]
+    public void ConvertBetweenTimeZones_Hawaii1()
+    {
+        var t = new DateTime(2024, 06, 17, 22, 24, 0, DateTimeKind.Unspecified);
+        var tz = TimeZoneInfo.FindSystemTimeZoneById("Central European Standard Time");
+        var ldt = new LocalDateTime(t, tz);
+        var hawaii = ldt.ToTimeZone(TimeZoneInfo.FindSystemTimeZoneById("Hawaiian Standard Time"));
+        hawaii.DateTime.Kind.Should().Be(DateTimeKind.Unspecified);
+        hawaii.ToDateTimeOffsetUtc().Should().Be(ldt.ToDateTimeOffsetUtc());
+        hawaii.ToDateTimeOffsetLocal().ToString("yyyy-MM-ddTHH:mm:ssK").Should().Be("2024-06-17T10:24:00-10:00");
+    }
+
+    [Fact]
+    public void ConvertBetweenTimeZones_Hawaii2()
+    {
+        var t = new DateTime(2024, 02, 17, 22, 24, 0, DateTimeKind.Unspecified);
+        var tz = TimeZoneInfo.FindSystemTimeZoneById("Central European Standard Time");
+        var ldt = new LocalDateTime(t, tz);
+        var hawaii = ldt.ToTimeZone(TimeZoneInfo.FindSystemTimeZoneById("Hawaiian Standard Time"));
+        hawaii.DateTime.Kind.Should().Be(DateTimeKind.Unspecified);
+        hawaii.ToDateTimeOffsetUtc().Should().Be(ldt.ToDateTimeOffsetUtc());
+        hawaii.ToDateTimeOffsetLocal().ToString("yyyy-MM-ddTHH:mm:ssK").Should().Be("2024-02-17T11:24:00-10:00");
+    }
+
+    // 
     [Fact]
     public void TestDateConstructor()
     {
diff --git a/TimeKeeping/DotNetThoughts.TimeKeeping/LocalDateTime.cs b/TimeKeeping/DotNetThoughts.TimeKeeping/LocalDateTime.cs
index d46b9fc..cc86d9b 100644
--- a/TimeKeeping/DotNetThoughts.TimeKeeping/LocalDateTime.cs
+++ b/TimeKeeping/DotNetThoughts.TimeKeeping/LocalDateTime.cs
@@ -34,6 +34,11 @@ public LocalDateTime(DateTime dateTime, TimeZoneInfo timeZoneInfo)
     public DateTime DateTime { get; }
     public TimeZoneInfo TimeZoneInfo { get; }
 
+    public LocalDateTime ToTimeZone(TimeZoneInfo newTz)
+    {
+        return new LocalDateTime(TimeZoneInfo.ConvertTime(DateTime, TimeZoneInfo, newTz), newTz);
+    }
+
     public LocalDateTime ToMidnight()
     {
         return new LocalDateTime(DateTime.Date, TimeZoneInfo);