SAN DIEGO — The Rock ‘N’ Roll Marathon is back for its 25th year, and runners are resting up for their big race.

Saturday will kick off the weekend with a 5k through Balboa Park, but runners are being warned parking is going to be more difficult than in previous years.

New bike lanes have shut down hundreds of parking spaces while Metropolitan Transit Service is trying to make up for the loss with runners utilizing mass transit.

“There’s going to be thousands of riders, we are expecting a higher-than-average rate, so it’s best to be prepared,” said Max Walther with the MTS.

Experts are telling runners to download the MTS pronto app to buy tickets seamlessly.

The Saturday 5K is expected to shut down roads from 5:30 a.m. to 10:30 a.m. in the Balboa Park area.

The official Rock ‘N’ Roll Marathon is set for Sunday. Roads and highways all over downtown San Diego are expected to be jammed from 5:30 a.m. to 3:15 p.m., so try to avoid the area if you can.

To all the runners out there, good luck, start slow and pick up the pace later.