diff --git a/check.py b/check.py
index 81e028f..39043d6 100755
--- a/check.py
+++ b/check.py
@@ -122,34 +122,126 @@ def normalize_url(url: str) -> str:
     return urlunparse(parsed_url._replace(netloc=normalized_netloc))
 
 
-def check_conference(
-    name: str, src_url: str, year: int
-) -> tuple[bool, str, str | None]:
-    """Check if conference is live."""
-    url = src_url.format(year=year)
-    past_url = src_url.format(year=year - 1)
-    try:
-        # SotM Baltics has an invalid TLS certificate, but we don't care
-        r = s.get(url, verify=False)
-    except requests.exceptions.ConnectionError:
-        return (False, "connection refused", None)
+def url_to_filename(url: str) -> str:
+    """
+    Convert a URL to a valid filename by replacing invalid characters with underscores.
 
-    not_here = find_not_here_message(r.text)
-    if (
-        len(r.text) < 2048
-        and 'http-equiv="refresh"' in r.text
-        and str(year) not in r.text
-    ):
-        return (False, "redirect to URL without year", r.url)
+    Args:
+        url (str): The URL to be converted.
 
-    if normalize_url(r.url) == normalize_url(past_url):
-        return (False, "redirect to previous year", r.url)
+    Returns:
+        str: A valid filename.
+    """
+    # Replace invalid characters with underscores
+    return re.sub(r'[\/:*?"<>|]', "_", url)
 
-    return (False, not_here, r.url) if not_here else (True, get_title(r.text), r.url)
+
+def parse_opengraph_tags(html: str) -> dict[str, str]:
+    """
+    Locate Open Graph meta tags, and return them as a dictionary.
+
+    Keys will match the name following 'og:', e.g. 'title', 'image', 'url', 'site_name'.
+    """
+    pattern = re.compile(
+        r'<meta\s+property="og:([^"]+)"\s+content="([^"]+)"\s*/?>', flags=re.IGNORECASE
+    )
+    matches = pattern.findall(html)
+
+    og_tags = {}
+    for prop, content in matches:
+        og_tags[prop] = content
+
+    return og_tags
+
+
+class Conference:
+    """Conference."""
+
+    name: str
+    src_url: str
+    year: int
+    response: None | requests.models.Response
+
+    def __init__(self, name: str, src_url: str, year: int):
+        """Init."""
+        self.name = name
+        self.src_url = src_url
+        self.year = year
+        self.response = None
+
+    @property
+    def url(self) -> str:
+        """Conference URL."""
+        return self.src_url.format(year=self.year)
+
+    @property
+    def past_url(self) -> str:
+        """URL for previous year."""
+        return self.src_url.format(year=self.year - 1)
+
+    def check(self) -> tuple[bool, str, str | None]:
+        """Check if conference is live."""
+        try:
+            # SotM Baltics has an invalid TLS certificate, but we don't care
+            r = s.get(self.url, verify=False)
+        except requests.exceptions.ConnectionError:
+            return (False, "connection refused", None)
+
+        self.response = r
+
+        filename = url_to_filename(self.url)
+        with open(os.path.join("sites", filename + ".html"), "w") as out:
+            out.write(r.text)
+
+        not_here = find_not_here_message(r.text)
+        if (
+            len(r.text) < 2048
+            and 'http-equiv="refresh"' in r.text
+            and str(self.year) not in r.text
+        ):
+            return (False, "redirect to URL without year", r.url)
+
+        if normalize_url(r.url) == normalize_url(self.past_url):
+            return (False, "redirect to previous year", r.url)
+
+        if not_here:
+            return (False, not_here, r.url)
+
+        return (True, get_title(r.text), r.url)
+
+    def og_tags(self) -> dict[str, str]:
+        """Open Graph tags."""
+        assert self.response
+        return parse_opengraph_tags(self.response.text)
+
+    def check_web_site(self) -> bool:
+        """Check if an individual web site is live."""
+        assert "{year}" in self.src_url
+        live, msg, redirect_to_url = self.check()
+        if not live:
+            return False
+
+        og = "".join(f"\n{key}: {value}" for key, value in self.og_tags().items())
+
+        if og:
+            og = "\n\nOpen Graph\n\n" + og
+
+        if redirect_to_url and normalize_url(redirect_to_url) == normalize_url(
+            self.url
+        ):
+            body = f"{self.name}\n{self.url}\n"
+        else:
+            body = f"{self.name}\n{self.url} redirects to {redirect_to_url}\n"
+
+        body += "Web page title: {msg}{og}" ""
+        send_mail(f"Conference site live: {self.name} - {self.year}", body)
+
+        return True
 
 
 def send_mail(subject: str, body: str) -> None:
     """Send an e-mail."""
+    return
     mail_from_address = config["mail"]["from_address"]
     mail_from_name = config["mail"]["from_name"]
     mail_to_address = config["mail"]["to_address"]
@@ -171,21 +263,10 @@ def send_mail(subject: str, body: str) -> None:
     s.quit()
 
 
-def check_conference_web_site(name: str, src_url: str, year: int) -> bool:
-    """Check if an individual web site is live."""
-    assert "{year}" in src_url
-    live, msg, redirect_to_url = check_conference(name, src_url, year)
-    url = src_url.format(year=year)
-    if live:
-        if redirect_to_url and normalize_url(redirect_to_url) == normalize_url(url):
-            body = f"{name}\n{url}\nWeb page title: {msg}"
-        else:
-            body = f"""{name}
-{url} redirects to {redirect_to_url}
-Web page title: {msg}"""
-        send_mail(f"Conference site live: {name} - {year}", body)
-
-    return live
+def check(name: str, src_url: str, year: int) -> bool:
+    """Check to see if conference site is live."""
+    conf = Conference(name, src_url, year)
+    return conf.check_web_site()
 
 
 def find_new_conference_web_sites(
@@ -201,8 +282,7 @@ def find_new_conference_web_sites(
         new += [
             {"conference": name, "year": year, "live": today}
             for year in (this_year, this_year + 1)
-            if (name, year) not in live_set
-            and check_conference_web_site(name, src_url, year)
+            if (name, year) not in live_set and check(name, src_url, year)
         ]
     return new