NOUN1はNOUN2(と/に)関係がある as “NOUN1 is related to NOUN2”
This grammatical expression is used to express that two entities have something to do with each other, share a connection with each other, are related in some way, etc.
When this phrasing is being used to modify a noun instead of forming a complete clause, the particle が in 関係がある is instead replaced by the particle の. Furthermore, the NOUN1は at the beginning of the construction is dropped, as the NOUN1 typically becomes the noun being modified, thus entire construction becomes NOUN2(と/に)関係のあるNOUN1 as “NOUN1 that has a connection to NOUN2.”
Bunka wa rekishi to fukai kankei ga arimasu.
(Culture has a deep connection with history.)
Shoku wa kenkou to kankei ga arimasukara asagohan o tabenakute wa dame desuyo.
(Your diet is related to your health, so it’s not good to skip breakfast.)
Kono happyou ni kankei no nai shitsumon o kikanaide kudasai.
(Please don’t ask any questions that don’t have anything to do with this announcement.)