But nowhere will be more impacted than Windsor, where the wedding is taking place.
Crowds are already starting to gather and with thousands more expected to descend on the Berkshire town officials are now warning expectant mums that it may be difficult getting to hospital.
As a result those mums-to-be who are near their due dates are being urged to contact their midwife.
“Pregnant women close to their due date are encouraged to speak to their midwives about what arrangements can be put in place, but rest assured their needs will be met and babies safely delivered,” a spokesperson from the royal Borough of Windsor and Maidenhead told Telegraph.
And it isn’t just pregnant women who have been urged to plan ahead.
Officials have also advised residents to stock up on essential medicines ahead of the nuptials as the crowds could make reaching a pharmacy difficult.
“Residents who live in Windsor are asked to order repeat prescriptions in advance to ensure they have supplies of medication,” the spokesman continued.
“Pharmacies in central Windsor will be open, but it may be difficult to get through the crowds into the town centre.”
“Residents are encouraged to make sure that whatever healthcare needs they have, they make adequate arrangements to prepare whatever they can before the weekend.”
The ceremony itself begins at 12pm and the carriage procession through the streets of Windsor take place shortly after 1pm and is due to last 25 minutes.
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