Indoor spots — tip: free Smithsonian museums are best right at opening (10am) before crowds.
Watkins Nature Center
Upper Marlboro · Prince George's · Nature center
IndoorFree- Ages: All ages
- Cost: Free
- Hours/season: Tue–Sat 10am–5pm, Sun 10am–4pm
Official site →Robinson Nature Center
Columbia · Howard · Nature center
IndoorOutdoor- Ages: Under 3 free
- Cost: Adults $5, kids 3–17 $3
- Hours/season: Official county page lists both Tue–Sun 9am–5pm and Wed–Sat 9am–5pm / Sun noon–5pm (parking gates); call 410-313-0400
Official site →Brookside Nature Center
Wheaton · Montgomery · Nature center
IndoorOutdoorFree- Ages: All ages
- Cost: Free
- Hours/season: Grounds sunrise–sunset; building Sat 10am–4pm, Sun noon–4pm
Official site →Brookside Gardens
Wheaton · Montgomery · Gardens / conservatory
IndoorOutdoorFree- Ages: All ages
- Cost: Free
- Hours/season: Gardens sunrise–sunset; conservatories 10am–5pm
Official site →Patuxent Research Refuge – National Wildlife Visitor Center
Laurel · Prince George's · Nature center / trails
IndoorOutdoorFree- Ages: All ages
- Cost: Free
- Hours/season: Visitor center Wed–Sat 10am–4pm; grounds sunrise–sunset
Official site →Chesapeake Children's Museum
Annapolis · Anne Arundel · Children's museum
Indoor- Ages: 1+ (under 1 free)
- Cost: $8 per person age 1+
- Hours/season: Daily 10am–4pm
Official site →Port Discovery Children's Museum
Baltimore · Baltimore City · Children's museum
Indoor- Ages: Under 1 free
- Cost: $25.95; advance tickets recommended
- Hours/season: Fall: Fri–Sat 10am–5pm, Sun 11am–5pm, Mon & Thu 10am–3pm
Official site →National Museum of Railroad History & Innovation (B&O)
Baltimore · Baltimore City · Train museum
Indoor- Ages: All ages (official page doesn't list a child age range or under-2 policy; ask at admissions)
- Cost: Adults $20, children $12; free on-site parking
- Hours/season: Daily 10am–4pm
Official site →Irvine Nature Center
Owings Mills · Baltimore County · Nature center
IndoorOutdoor- Ages: 5 & under free
- Cost: $5 per person age 6+
- Hours/season: Tue–Sun 9am–5pm
Official site →National Museum of Natural History
Washington · DC · Museum
IndoorFree- Ages: All ages
- Cost: Free, no tickets
- Hours/season: Daily 10am–5:30pm
Official site →National Air and Space Museum
Washington · DC · Museum
IndoorFree- Ages: All ages
- Cost: Free timed-entry tickets
- Hours/season: Daily 10am–5:30pm
Official site →Wegmans Wonderplace (American History Museum)
Washington · DC · Toddler play space
IndoorFree- Ages: 0–6
- Cost: Free same-day timed tickets
- Hours/season: Wed–Sun 10am–4pm
Official site →HCLS 'Time For Us: Toddler Play & Learn'
Howard County · Howard · Library program
IndoorFree- Ages: 18–35 months with adult
- Cost: Free; tickets required
- Hours/season: Fri Oct 16, 2026, 10:30am
Official site →MCPL Family Storytime at White Oak + Stay 'n Play
Silver Spring · Montgomery · Library story time
IndoorFree- Ages: 0–6
- Cost: Free
- Hours/season: Sat Oct 17, 2026, 10:30–11:30am
Official site →