diff -r 3528cc01c4d9 Lib/test/test_ast.py
--- a/Lib/test/test_ast.py	Sun Dec 30 22:15:37 2012 +0100
+++ b/Lib/test/test_ast.py	Sun Dec 30 22:23:34 2012 +0100
@@ -289,6 +289,25 @@
         self.assertRaises(TypeError, ast.Num, 1, 2)
         self.assertRaises(TypeError, ast.Num, 1, 2, lineno=0)
 
+    def test_multi_line_docstring_col_offset_and_lineno_issue16806(self):
+        node = ast.parse(
+            '"""line one\nline two"""\n\n'
+            'def foo():\n  """line one\n  line two"""\n\n'
+            '  def bar():\n    """line one\n    line two"""\n'
+            '  """line one\n  line two"""\n'
+            '"""line one\nline two"""\n\n'
+        )
+        self.assertEqual(node.body[0].col_offset, 0)
+        self.assertEqual(node.body[0].lineno, 1)
+        self.assertEqual(node.body[1].body[0].col_offset, 2)
+        self.assertEqual(node.body[1].body[0].lineno, 5)
+        self.assertEqual(node.body[1].body[1].body[0].col_offset, 4)
+        self.assertEqual(node.body[1].body[1].body[0].lineno, 9)
+        self.assertEqual(node.body[1].body[2].col_offset, 2)
+        self.assertEqual(node.body[1].body[2].lineno, 11)
+        self.assertEqual(node.body[2].col_offset, 0)
+        self.assertEqual(node.body[2].lineno, 13)
+
     def test_module(self):
         body = [ast.Num(42)]
         x = ast.Module(body)
diff -r 3528cc01c4d9 Parser/parsetok.c
--- a/Parser/parsetok.c	Sun Dec 30 22:15:37 2012 +0100
+++ b/Parser/parsetok.c	Sun Dec 30 22:23:34 2012 +0100
@@ -155,6 +155,8 @@
         size_t len;
         char *str;
         int col_offset;
+        int lineno;
+        int line_start;
 
         type = PyTokenizer_Get(tok, &a, &b);
         if (type == ERRORTOKEN) {
@@ -190,13 +192,19 @@
 
 #ifdef PY_PARSER_REQUIRES_FUTURE_KEYWORD
 #endif
-        if (a >= tok->line_start)
-            col_offset = a - tok->line_start;
+        /* Nodes of type STRING, especially multi line strings
+           must be handled differently in order to get both
+           the starting line number and the column offset right.
+           (cf. issue 16806) */
+        lineno = type == STRING ? tok->first_lineno : tok->lineno;
+        line_start = type == STRING ? tok->multi_line_start : tok->line_start;
+        if (a >= line_start)
+            col_offset = a - line_start;
         else
-            col_offset = -1;
+             col_offset = -1;
 
         if ((err_ret->error =
-             PyParser_AddToken(ps, (int)type, str, tok->lineno, col_offset,
+             PyParser_AddToken(ps, (int)type, str, lineno, col_offset,
                                &(err_ret->expected))) != E_OK) {
             if (err_ret->error != E_DONE) {
                 PyObject_FREE(str);
diff -r 3528cc01c4d9 Parser/tokenizer.c
--- a/Parser/tokenizer.c	Sun Dec 30 22:15:37 2012 +0100
+++ b/Parser/tokenizer.c	Sun Dec 30 22:23:34 2012 +0100
@@ -1529,6 +1529,14 @@
         int quote = c;
         int triple = 0;
         int tripcount = 0;
+
+        /* Nodes of type STRING, especially multi line strings
+           must be handled differently in order to get both
+           the starting line number and the column offset right.
+           (cf. issue 16806) */
+        tok->first_lineno = tok->lineno;
+        tok->multi_line_start = tok->line_start;
+
         for (;;) {
             c = tok_nextc(tok);
             if (c == '\n') {
diff -r 3528cc01c4d9 Parser/tokenizer.h
--- a/Parser/tokenizer.h	Sun Dec 30 22:15:37 2012 +0100
+++ b/Parser/tokenizer.h	Sun Dec 30 22:23:34 2012 +0100
@@ -31,6 +31,8 @@
     int pendin;         /* Pending indents (if > 0) or dedents (if < 0) */
     char *prompt, *nextprompt;          /* For interactive prompting */
     int lineno;         /* Current line number */
+    int first_lineno;   /* First line of a single line or multi line string
+                           expression (cf. issue 16806) */
     int level;          /* () [] {} Parentheses nesting level */
             /* Used to allow free continuations inside them */
     /* Stuff for checking on different tab sizes */
@@ -46,6 +48,9 @@
     char *encoding;
     int cont_line;          /* whether we are in a continuation line. */
     const char* line_start;     /* pointer to start of current line */
+    const char* multi_line_start; /* pointer to start of first line of
+                                     a single line or multi line string 
+                                     expression (cf. issue 16806) */
 #ifndef PGEN
     PyObject *decoding_readline; /* codecs.open(...).readline */
     PyObject *decoding_buffer;