diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..6bcb5da
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,9 @@
+# 0.1.3
+
+- Update dependency versions
+- Correct definition of the error struct (add `impl Error`)
+- Add unit tests for the error struct
+
+# 0.1.2
+
+Initial release
diff --git a/Cargo.toml b/Cargo.toml
index 788092f..0e2e21b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "latlon"
-version = "0.1.2"
+version = "0.1.3"
 authors = ["Ondřej Hruška <ondra@ondrovo.com>"]
 description = "Parse latitude/longitude from many common formats"
 edition = "2018"
@@ -11,6 +11,6 @@ categories = ["parser-implementations", "science"]
 license = "MIT"
 
 [dependencies]
-geo-types = "0.5.0"
-regex = "1.3.7"
-lazy_static = "1.4.0"
+geo-types = "0.7"
+regex = "1"
+lazy_static = "1.4"
diff --git a/src/errors.rs b/src/errors.rs
index 241ad92..e7ae664 100644
--- a/src/errors.rs
+++ b/src/errors.rs
@@ -1,5 +1,5 @@
 use std::fmt;
-use std::fmt::{Display, Formatter};
+use std::fmt::{Display, Formatter, Debug};
 use std::num::ParseFloatError;
 
 #[derive(Debug)]
@@ -17,11 +17,20 @@ impl Display for ParseErrorInternal {
     }
 }
 
-#[derive(Debug)]
-pub struct GeoParseError<T: AsRef<str> + Display>(pub T);
+pub struct GeoParseError<T: AsRef<str>>(pub T);
+
+impl<T: AsRef<str>> Display for GeoParseError<T> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        write!(f, "Error parsing coordinates from {}", self.0.as_ref())
+    }
+}
 
-impl<T: AsRef<str> + Display> Display for GeoParseError<T> {
+impl<T : AsRef<str>> Debug for GeoParseError<T> {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
-        write!(f, "Error parsing coordinates from {}", self.0)
+        f.debug_tuple("GeoParseError")
+            .field(&self.0.as_ref())
+            .finish()
     }
 }
+
+impl<T : AsRef<str>> std::error::Error for GeoParseError<T> {}
diff --git a/src/tests.rs b/src/tests.rs
index c17ee35..3f52f28 100644
--- a/src/tests.rs
+++ b/src/tests.rs
@@ -1,4 +1,4 @@
-use crate::{parse, parse_lat, parse_lng};
+use crate::{parse, parse_lat, parse_lng, GeoParseError};
 use geo_types::Point;
 
 #[test]
@@ -472,3 +472,18 @@ fn d() {
     parse_lng(r#"-180°"#).unwrap();
     parse_lng(r#"1°"#).unwrap();
 }
+
+#[test]
+fn error() {
+    let e = GeoParseError("Hello");
+    assert_eq!("GeoParseError(\"Hello\")", format!("{:?}", e));
+    assert_eq!("GeoParseError(\n    \"Hello\",\n)", format!("{:#?}", e));
+
+    let e = GeoParseError("Hello2".to_string());
+    assert_eq!("GeoParseError(\"Hello2\")", format!("{:?}", e));
+    assert_eq!("GeoParseError(\n    \"Hello2\",\n)", format!("{:#?}", e));
+
+    let e = GeoParseError(std::borrow::Cow::Owned("Foo".to_string()));
+    assert_eq!("GeoParseError(\"Foo\")", format!("{:?}", e));
+    assert_eq!("GeoParseError(\n    \"Foo\",\n)", format!("{:#?}", e));
+}