Controversial car parking charges were introduced at Wrexham Maelor Hospital on Monday, causing traffic problems for commuters.
Pay-and-display parking has been introduced at the hospital
Long queues built up around the town centre site as staff, patients and visitors tried to find a space.
Managers at the North East Wales NHS Trust admit there were "teething problems" during rush hour.
The introduction of parking charges at Glan Clwyd Hospital in Bodelwyddan have already been delayed for a week.
Wrexham Maelor Hospital spokesman Andy Scotson said:"It was a bit difficult between 8.30 and 9 o clock.
"We did cause some congestion but having said that the big car park by the main entrance had lots of spaces".
The aim of the scheme is to keep parking in the central area of the hospital for patients while staff will be forced to park around the edges.
Staff have to pay £52 a year for a permit but there is a 50% discount for those earning less than £20,000.
"The charges are about funding the scheme, not about raising funds for the hospital," Mr Scotson added.
Meanwhile, parking charges are to be introduced at nearby Glan Clwyd Hospital on Tuesday for patients and visitors after a week-long delay.
Managers said the delay for patients and visitors for a week was to let them get used to the idea, and for staff for three months for talks under a health trust grievance procedure.
Staff at the hospital staged a protest over the new charging system in August but Conwy and Denbighshire NHS Trust said the scheme was necessary to ease traffic congestion at the site.