The Shulchan Aruch · Orach Chayim
אורח חיים כ״גOrach Chayim 23
Siman 23 of 697 in Orach Chayim — 4 se'ifim
הלכות ציציתLaws of Tzitzit· siman 23
Se’if 1א׳
מֻתָּר לִכָּנֵס בְּבֵית הַקְּבָרוֹת וְהוּא לָבוּשׁ צִיצִית, וְהוּא שֶׁלֹּא יְהֵא נִגְרָר עַל הַקְּבָרוֹת אֲבָל אִם הוּא נִגְרָר עַל הַקְּבָרוֹת אָסוּר מִשּׁוּם לוֹעֵג לָרָשׁ, בַּמֶּה דְּבָרִים אֲמוּרִים, בִּימֵיהֶם שֶׁהָיוּ מְטִילִים צִיצִית בַּמַּלְבּוּשׁ שֶׁלּוֹבְשִׁים לְצֹרֶךְ עַצְמָם, אֲבָל אָנוּ שֶׁאֵין אָנוּ מְכַוְּנִים בָּהֶם אֶלָּא לְשֵׁם מִצְוָה אָסוּר אֲפִלּוּ אֵינָם נִגְרָרִים, וְהָנֵי מִילֵי כְּשֶׁהַצִּיצִיּוֹת מְגֻלִּים אֲבָל אִם הֵם הַמְכֻסִים מֻתָּר.
The Laws of ציצית In A Cemetery. Containing 4 Se'ifim: It is permissible to enter a cemetery while wearing ציצית, as long as they are not dragging on the graves. But if they are dragging on the graves it is forbidden because of "mocking the poor". In what [case] are these words said (ie. when does this apply)? In their times (ie. the times of the Talmud) when they would place ציצית on their garments that were needed for them (ie. their daily garments... and if they were to remove them they would be left unclothed). But we who only intend to wear them (the ציצית) for the sake of the mitzvah, it is forbidden even if they are not dragging [on the graves]. And these words (ie. all this that we said) are [referring to] when the ציצית are revealed, but if they were covered up then it permitted.
Se’if 2ב׳
יֵשׁ נוֹהֲגִים לִקְשֹׁר ב' צִיצִיּוֹת שֶׁבִּשְׁנֵי כְּנָפַיִם זֶה עִם זֶה כְּשֶׁנִּכְנָסִים לְבֵית הַקְּבָרוֹת, וְלֹא הוֹעִילוּ כְּלוּם בְּתַקָּנָתָן.
There are some who have a practice to tie the 2 ציצית from 2 of the corners together when they enter into the cemetery. But they do not accomplish anything by doing this.
Se’if 3ג׳
הַנִּכְנָס תּוֹךְ ד' אַמּוֹת שֶׁל מֵת אוֹ שֶׁל קֶבֶר, דִּינוֹ כְּנִכְנָס לְבֵית הַקְּבָרוֹת.
One who enters within 4 cubits of a dead body or a grave, the same law applies [to him] as one entering a cemetery.
Shulchan Aruch, Orach Chayim — Torat Emet 363 edition, via Sefaria — public domain
English: Sefaria Community Translation — CC0