Catching the bus outside the Grosvenor-Strathmore Metro station on busy Rockville Pike is a breeze now. A ramp from the rail station leads straight to a comfortable bench and spacious bus shelter. But it wasn’t always that easy.

An old, rusting shelter was replaced and a concrete ramp installed to make the bus stop more accessible for wheelchairs as part of a 10-year plan by Montgomery County, Md., to upgrade 3,400 bus stops that were in desperate need of improvement.

Seven years into the program, upgrades have been made to 3,025 stops, including the one at the Grosvenor-Strathmore Metro station in north Bethesda. County and federal officials gathered there Thursday to mark the 25th anniversary of the Americans with Disabilities Act — which actually occurs Sunday — and celebrate the county’s progress in making its bus stops more accessible.

The event, marked with balloons and speeches, also was a reminder of the work still ahead to make bus stops safe and attractive spaces for people with mobility problems in the Washington region and beyond.

“There are still barriers that prevent equal access to opportunity,” said Therese W. McMillan, acting administrator of the Federal Transit Administration. “One of the most pervasive challenges for public transportation has been the ability to actually get to the bus stop or the rail station.”

Although 99.8 percent of public buses in the United States are accessible to people who have mobility problems, broken sidewalks — or an absence of sidewalks — and curb cuts that are in disrepair remain obstacles, McMillan said.

In many parts of the Washington region, bus riders encounter challenges such as bus-stop signs beside six-lane roads that have no sidewalks or ramps.

Of the region’s 19,000 bus stops, about one-third — or 6,500 — are inaccessible to wheelchair users and others with limited mobility, according to Metro. And even where improvements have been made, many stops fall short of true accessibility because they lack walkable pathways, accessibility and transit officials say.

“We have to look at expanding the idea of what accessibility means,” said Brian Miller, a member of Metro’s Accessibility Advisory Committee representing the city of Alexandria, Va. “It means that once I get off the bus, I can actually get somewhere. I can get down the block and get across the street. Otherwise, you are just in a little island and that’s not really accessible in the more meaningful way.”

Metro has been working with the region’s jurisdictions, which are responsible for upgrades, to prioritize improvements at bus stops that get the heaviest use and where there are greater numbers of customers using transportation services for those with disabilities, said Christian Kent, assistant general manager for Metro’s Access Services department.

“There has been a lot of progress,” he said, noting that although Montgomery County leads the region in upgrading bus-stop accessibility, other area jurisdictions also are making improvements.

Metro last year expanded its accessibility standards for bus stops, saying that improvements should go beyond the ADA requirements of adding at least a 5-by-8-foot paved surface that connects to the curb. Metro guidelines say improvements also should incorporate a clear pathway serving each bus stop.

Under the ADA, Metro is required to provide equal access to public transit for those with disabilities. The transit system also encourages nearly 6,000 people with a disabilities to use rail and bus instead of the more costly door-to-door MetroAccess van.

For Metro, bus-stop improvements are key to reducing demand for MetroAccess. If customers with disabilities have adequate access to the bus and rail system, they are more likely to opt for that fixed route, saving the agency thousands of dollars. It costs Metro an average of $50 to provide a MetroAccess trip, compared with $3-$4 per passenger for bus and rail service.

But making bus stops accessible can also be expensive. Improvements, including design and construction, cost about $10,000 per stop, according to Metro. And that does not include shelters or other equipment such as audio features for the visually impaired.

Advocates for people with disabilities say retrofitting bus stops is a first step in providing good commuting options. But other challenges remain. In the District, for example, traffic sometimes makes it difficult for buses to stop close to the curb and extend their lifts. Most buses can accommodate only two passengers in wheelchairs, and sometimes that means wheelchair users must wait for other buses. And many bus stops still lack audible features for the blind.

“I come to a stop and I need to know which buses stop there, what times and where they are going,” said Miller, who is blind and depends on public transit to travel between his home in Alexandria and his job at the Department of Education in the District. “It is a work in progress.”

In Montgomery, the $11 million, 10-year improvement project began in 2008, after a study identified 3,400 of the county’s 5,400 bus stops as needing upgrades. Seven years later, the county has built 1,255 ramps at 826 intersections, 85,618 square feet of sidewalks, and concrete pads at 2,474 bus stops.

“We were able to do so in the midst of a great recession and other economic challenges,” Montgomery County Executive Isiah Leggett (D) said Thursday.

Montgomery has provided significant local funding, but other jurisdictions in the region depend mostly on federal grants to make improvements. There are also jurisdictional and right-of-way challenges, although Metro officials say major improvements have been made in recent years.

Last year, Metro said it had received a $1.2 million federal grant to improve 88 stops in Virginia and Maryland: 17 in the city of Alexandria; 31 in Arlington County; six in Fairfax County; and 34 in Prince George’s County, Md.

The improvements address more than just the needs of people with disabilities, advocates say, noting that they ultimately make the roads safer for all pedestrians in a time when more people choose to commute by bus.

“As the region gets closer to having all the bus stops accessible, public transit is going to become more attractive, and the bus services are going to get more use,” Kent said. “That benefits the customer, it is a cost-effective way to get around, and it is good for the environment.”