diff --git a/src/common.rs b/src/common.rs
index 1ef2fbd..d640994 100644
--- a/src/common.rs
+++ b/src/common.rs
@@ -36,7 +36,6 @@ impl TryFrom<geo_traits::Dimensions> for WKBDimension {
             Xyz | Unknown(3) => Self::Xyz,
             Xym => Self::Xym,
             Xyzm | Unknown(4) => Self::Xyzm,
-            // TODO: switch to tryfrom
             Unknown(n_dim) => {
                 return Err(WKBError::General(format!(
                     "Unsupported number of dimensions: {}",
@@ -86,7 +85,12 @@ impl WKBType {
         let geometry_type = match byte_order {
             0 => reader.read_u32::<BigEndian>().unwrap(),
             1 => reader.read_u32::<LittleEndian>().unwrap(),
-            other => panic!("Unexpected byte order: {}", other),
+            other => {
+                return Err(WKBError::General(format!(
+                    "Unexpected byte order: {}",
+                    other
+                )))
+            }
         };
         Self::try_from_u32(geometry_type)
     }
diff --git a/src/writer/polygon.rs b/src/writer/polygon.rs
index 7bfd28b..3cd4ca4 100644
--- a/src/writer/polygon.rs
+++ b/src/writer/polygon.rs
@@ -11,9 +11,9 @@ pub fn polygon_wkb_size(geom: &impl PolygonTrait) -> usize {
 
     let each_coord = geom.dim().size() * 8;
 
-    // TODO: support empty polygons where this will panic
-    let ext_ring = geom.exterior().unwrap();
-    sum += 4 + (ext_ring.num_coords() * each_coord);
+    if let Some(ext_ring) = geom.exterior() {
+        sum += 4 + (ext_ring.num_coords() * each_coord);
+    }
 
     for int_ring in geom.interiors() {
         sum += 4 + (int_ring.num_coords() * each_coord);
@@ -46,18 +46,22 @@ fn write_polygon_content<W: Write, B: ByteOrder>(
     writer.write_u32::<LittleEndian>(wkb_type.into())?;
 
     // numRings
-    // TODO: support empty polygons where this will panic
-    let num_rings = 1 + geom.num_interiors();
+    let num_rings = if geom.exterior().is_some() {
+        1 + geom.num_interiors()
+    } else {
+        0
+    };
     writer.write_u32::<B>(num_rings.try_into().unwrap())?;
 
-    let ext_ring = geom.exterior().unwrap();
-    writer.write_u32::<B>(ext_ring.num_coords().try_into().unwrap())?;
+    if let Some(ext_ring) = geom.exterior() {
+        writer.write_u32::<B>(ext_ring.num_coords().try_into().unwrap())?;
 
-    for coord in ext_ring.coords() {
-        writer.write_f64::<B>(coord.x())?;
-        writer.write_f64::<B>(coord.y())?;
-        if geom.dim().size() == 3 {
-            writer.write_f64::<B>(coord.nth_unchecked(2))?;
+        for coord in ext_ring.coords() {
+            writer.write_f64::<B>(coord.x())?;
+            writer.write_f64::<B>(coord.y())?;
+            if geom.dim().size() == 3 {
+                writer.write_f64::<B>(coord.nth_unchecked(2))?;
+            }
         }
     }