diff --git a/NEWS b/NEWS
index 1be6c83a2..0ab0b395c 100644
--- a/NEWS
+++ b/NEWS
@@ -19,7 +19,10 @@ Instead, use the symbol values `none', `line', or `block', respectively,
 as arguments to the `setvbuf' function.
 
 * Incompatible changes
+** Remove `scm_set_port_mark'
 
+Port mark functions have not been called since the switch to the BDW
+garbage collector.
 
 
 Changes in 2.1.2 (changes since the 2.1.1 alpha release):
diff --git a/doc/ref/api-io.texi b/doc/ref/api-io.texi
index e1501e2b4..80a227202 100644
--- a/doc/ref/api-io.texi
+++ b/doc/ref/api-io.texi
@@ -2303,14 +2303,6 @@ A pointer to a NUL terminated string: the name of the port type.  This
 is the only element of @code{scm_ptob_descriptor} which is not
 a procedure.  Set via the first argument to @code{scm_make_port_type}.
 
-@item mark
-Called during garbage collection to mark any SCM objects that a port
-object may contain.  It doesn't need to be set unless the port has
-@code{SCM} components.  Set using
-
-@deftypefun void scm_set_port_mark (scm_t_bits tc, SCM (*mark) (SCM port))
-@end deftypefun
-
 @item free
 Called when the port is collected during gc.  It
 should free any resources used by the port.
diff --git a/libguile/ports.c b/libguile/ports.c
index da8b4d22c..3f1b5b1c5 100644
--- a/libguile/ports.c
+++ b/libguile/ports.c
@@ -267,12 +267,6 @@ scm_make_port_type (char *name,
   return scm_tc7_port + ptobnum * 256;
 }
 
-void
-scm_set_port_mark (scm_t_bits tc, SCM (*mark) (SCM))
-{
-  scm_c_port_type_ref (SCM_TC2PTOBNUM (tc))->mark = mark;
-}
-
 void
 scm_set_port_free (scm_t_bits tc, size_t (*free) (SCM))
 {
diff --git a/libguile/ports.h b/libguile/ports.h
index d8527be5f..f6c217fe3 100644
--- a/libguile/ports.h
+++ b/libguile/ports.h
@@ -184,7 +184,6 @@ typedef enum scm_t_port_type_flags {
 typedef struct scm_t_ptob_descriptor
 {
   char *name;
-  SCM (*mark) (SCM);
   size_t (*free) (SCM);
   int (*print) (SCM exp, SCM port, scm_print_state *pstate);
   SCM (*equalp) (SCM, SCM);
@@ -224,7 +223,6 @@ SCM_API scm_t_bits scm_make_port_type (char *name,
 				       void (*write) (SCM port, 
 						      const void *data,
 						      size_t size));
-SCM_API void scm_set_port_mark (scm_t_bits tc, SCM (*mark) (SCM));
 SCM_API void scm_set_port_free (scm_t_bits tc, size_t (*free) (SCM));
 SCM_API void scm_set_port_print (scm_t_bits tc,
 				 int (*print) (SCM exp,