marshallString(th, you.level_type_origin);

        you.level_type_tag = unmarshallString(th);

    {
        you.level_type_origin = unmarshallString(th);
        you.level_type_tag    = unmarshallString(th);
    }

    std::string neworigin =
        env.markers.property_at(you.pos(), MAT_ANY, "dstorigin");
    you.level_type_origin = "";

    // Lua scripts explicitly set level_type_origin, so use that.
    if (!you.level_type_origin.empty())
        neworigin = you.level_type_origin;

    if (!neworigin.empty())
        you.level_type_origin = neworigin;
    else if (!you.level_type_name.empty())
    {
        std::string lname = lowercase_string(you.level_type_name);
        std::string article, prep;
        if (starts_with(lname, "level "))
            prep = "on ";
        else
            prep = "in ";
        if (starts_with(lname, "a ") || starts_with(lname, "an ")
            || starts_with(lname, "the ") || starts_with(lname, "level "))
        {
            ; // Doesn't need an article
        }
        else
        {
            char letter = you.level_type_name[0];
            if (isupper(letter))
                article = "the ";
            else if (is_vowel(letter))
                article = "an ";
            else
                article = "a ";
        }
        you.level_type_origin  = prep + article + you.level_type_name;
    }

}
LUAFN(dgn_set_level_type_origin)
{
    if (you.level_type != LEVEL_PORTAL_VAULT)
    {
        luaL_error(ls, "Can only set level type origin on portal vaults");
        return(0);
    }
    if (!lua_isstring(ls, 1))
    {
        luaL_argerror(ls, 1, "Expected string for level type origin");
        return(0);
    }
    you.level_type_origin = luaL_checkstring(ls, 1);
    return(0);

    { "set_level_type_origin", dgn_set_level_type_origin },

#define PORTAL_VAULT_ORIGIN_KEY "portal_vault_origin"

}
void _origin_set_portal_vault(item_def &item)
{
    if (you.level_type != LEVEL_PORTAL_VAULT)
        return;
    item.props[PORTAL_VAULT_ORIGIN_KEY] = you.level_type_origin;

        _origin_set_portal_vault(item);

    _origin_set_portal_vault(item);

    _origin_set_portal_vault(item);

        _origin_set_portal_vault(item);

    if (place_type(item.orig_place) == LEVEL_PORTAL_VAULT
        && item.props.exists(PORTAL_VAULT_ORIGIN_KEY))
    {
        return item.props[PORTAL_VAULT_ORIGIN_KEY].get_string();
    }
    

  // Item origin string for items from portal vaults, so that dumps
  // can have origins like "You found it in on level 2 of a ziggurat".
  // Will be set relative to level_type_name if not explicitly set.
  std::string level_type_origin;

                                     dst = "sewer", floor = "stone_arch" }]])

                                     dst = "sewer",
                                     dstorigin = "in the sewers",
                                     floor = "stone_arch" }]])

  dgn.set_level_type_origin("on level " .. zig().depth .. " of a ziggurat")

      dstorigin = "on level 1 of a ziggurat",

end

end

Portal vaults can be particularly thematic, using specialised monster 
sets, fitting loot, coloured dungeon features etc. Avoid death traps; 
it is no fun to enter a vault, unable to leave and be killed outright.
Randomise in order to provide fun and reduce spoiler effects. For portal
vaults, it is desirable to have several different layouts (ideally each
of the maps has some randomisation on its own). Often, it is a good idea
to skew the map distribution: e.g. with four destination vaults, weights
like 40,30,20,10 might be more interesting than 25,25,25,25.

If you want the place name displayed while in the vault to be different
than the destination name, then you can give one_way_stair() a "dstname"
parameter.  If you want the place origin for items in a character
dump to be different than the default you can give one_way_stair a
"dstorigin" parameter (i.e., dstname = "garden", dstorigin = "in the gardens").
You can dynamically change the origin string using the lua function
dgn.set_level_type_origin().