Since Gunpowder Falls State Park crosses Bel Air Rd at the Little and Big Gunpowder Rivers, you need to be more specific. However, if you look at the Central Gunpowder trail maps at the DNR webpage, the maps will indicate which trails are not open to biking.

We were in the Hammerman area which is where the beach is. There is a food concession stand indoors. We brought some water and a picnic lunch. There are picnic tables everywhere. The address to get to the Hammerman Beach area is 7200 Graces Quarters Rd. You can google that address to get exact directions. There is a fee for resident and non resident ( per person) to get into the park. Pets on leashes are welcome but you cannot bring them on the sandy portion only the lawn area(s). Here is the pet policy: Park Rules All pets must be licensed and have all required vaccinations, including a rabies vaccination. Pets must be leashed. Pets may be off-leash and under voice control while swimming in designated areas or hunting (with the appropriate permit). Pet owners must clean up after their pet. Waste disposal containers are available in most areas. Service animals are permitted in all pedestrian areas. Pets, with the exception of service animals, are not allowed in park buildings. Pets, with the exception of service animals, are not allowed in playgrounds. Pet owners must obey all park signs that prohibit the entry of pets into specific areas. Excessive barking is not permitted in any park area, especially during campground "quiet hours" (10:00 p.m.- 7:00 a.m.). Bring your towels, a picnic lunch and spending money; maybe $25. There are tons of food venues outside of the Park if you would prefer to eat before entering. If you leave the park you have to pay to get back.