diff --git a/docs/HTTP3.md b/docs/HTTP3.md
index f063ab4f9..06783c007 100644
--- a/docs/HTTP3.md
+++ b/docs/HTTP3.md
@@ -75,8 +75,14 @@ you'll just get ld.so linker errors.
 
 ## Invoke from command line
 
+Use HTTP/3 directly:
+
     curl --http3 https://nghttp2.org:8443/
 
+Upgrade via Alt-Svc:
+
+    curl --alt-svc altsvc.cache https://quic.aiortc.org/
+
 # quiche version
 
 ## build