There are some mirrors of this page that might be closer to you, or just generally faster.
Canada (Sandelman Software Works)
https://www.ca.tcpdump.org (master)
US (Wireshark)
https://www.us.tcpdump.org
Germany (credit)
https://www.de.tcpdump.org
The web site is also on github at: https://github.com/the-tcpdump-group/tcpdump-htdocs

If you can offer additional mirrors, please contact tcpdump-workers@lists.tcpdump.org.