Flyers from Wolverhampton Council have been distributed telling residents over 25 years old who live or work in the city they can attend without an appointment.
Both the Pfizer and Oxford vaccines are being offered at the pop-up centre at Phoenix Park car park in Dudley Road.
Those awaiting first or second doses can attend, though anyone awaiting their follow-up jab must have received their first dose at least eight weeks ago.
The leaflet also said: "If you are over 25 and live with other adults, they can come with you to have their vaccine at the same time."
As a result large queues quickly formed at the vaccination centre on Sunday, with the site open until 7pm.