Creaking Victorian lines will be unable to cope with growing demand as the country's population continues to grow, he will tell a HS2 conference.
Mr Grayling will say: "We're not backing away from HS2. The case is as strong as ever.
"We need this railway. And if we're going to build it, let's make it state-of-the-art, fit for the decades of growth ahead.
"So that in 2033, we no longer have a rail network with a Victorian heart but a network with an Elizabethan heart, able to deliver everything we expect of a 21st century transport system."
MPs warned last month that ministers must set out a realistic timetable for delivering HS2.
The Public Accounts Committee (PAC) was ''not convinced'' that the target for completing phase one between London and the West Midlands by December 2026 will be met.
Its report also warned that cost estimates for phase two, which takes it from Birmingham to Manchester and Leeds, are ''still volatile'' and exceed available funding by £7 billion.
Mr Grayling will announce £70m of funding for road safety and support for communities affected by the line to the Midlands.
He will say: "We need HS2 now more than ever.
"We need it for the capacity it will bring on the routes between London, the West Midlands, Crewe, Leeds and Manchester, as well as the space it'll create elsewhere on our transport network.
"We need it for the boost it will give to our regional and national economies.
"And we need it for the jobs it will create, and for the way it will link our country together."
He will add: "We're facing a rapidly approaching crunch-point.
"In the last 20 years alone, the number of people travelling on our railways has more than doubled.
"And demand is set to increase still further. And it's not just about crowding in the carriages - it's also about crowding on the tracks themselves. Our rail network is the most intensively used of any in Europe."
England's best views
England's best views
As one of Northumberland's most iconic buildings, Bamburgh Castle sits proudly on a natural throne high above the coastline. If the tide is low you can admire the imposing castle from the beach below and even enjoy flying a kite. Trek up the hill to the dramatic site, which is one of the largest inhabited castles in the country and explore its rich history, discover the different areas like the Medieval Kitchen, the Keep and the King's Hall, and stop for tasty Northumberland treats in the Clock Tower Tea Rooms.
If you're looking for a fun seaside attraction for the whole family to enjoy, it's Blackpool Tower. Here you can ascend the 518-foot structure modelled on Paris's Eiffel Tower, step onto the SkyWalk across metres of glass at the top of the tower and hit the dancefloor at The Blackpool Tower Ballroom. Once you've experienced the panoramic views of Blackpool from a height, hit the miles of golden sand to see the iconic landmark in all its glory.
This beautiful residential road with 30 houses laid out in a crescent in the city of Bath was designed by architect John Wood the Younger and built between 1767 and 1774. The Royal Crescent is one of the country's finest examples of Georgian architecture and is Grade I listed with a hotel, museum, houses and offices located in the buildings. The Royal Victoria Park nearby is a location for the launch of hot air balloons - ideal if you're looking for a good photo opportunity or to see the road from the sky.
It's hard to beat the romantic grandeur of the World Heritage Site Hadrian's Wall. The famous stretch built by the Roman Emperor Hadrian in AD122 took soldiers six years to complete and was 73 miles long on what is today the border of England and Scotland. Housesteads Fort, one of the best preserved Roman forts is a popular historical site along the Wall. Walk the magnificent 73-mile Hadrian's Wall Path and discover the brilliant views over the open countryside. Looking for somewhere to sleep?
London's giant Ferris wheel is the ultimate spot to see the capital at its best. Get a good view of Big Ben, St Paul's Cathedral, Tower Bridge and beyond. On a clear day you can see around 25 miles from the top of the London Eye - that's as far as Windsor Castle! The wheel moves 26cm per second and each rotation takes around 30 minutes. It's one of the tallest structures in London at 135m and one of the city's most popular attractions. Hop on board one of the 32 capsules and see the views for yourself!
The chalk cliffs that make up The Seven Sisters by the English Channel are part of the South Downs in East Sussex. They're gradually being eroded by the sea and the peaks and dips are individually named Haven Brow, Short Brow, Rough Brow, Brass Point, Flagstaff Brow, Bailey's Hill and Went Hill. The natural beauty of The Seven Sisters has been recognised by filmmakers with the stunning cliffs featuring in Robin Hood: Prince of Thieves and Atonement. Want somewhere to stay?
As one of the most famous megalithic monuments in the world, Stonehenge is an icon of prehistoric Britain dating back an astonishing 5,000 years. Stonehenge took a whopping 1,600 years to build - but the purpose of the attraction remains a mystery. You can get a good look from outside the main enclosure or pay to get really close to the stones. If you want a view that will make you feel fear, excitement and awe all in one go, Stonehenge is the place to visit!
With a variety of breathtaking landscapes, large old limestone field barns and plenty of white sheep, Swaledale, part of the Yorkshire Dales National Park shows rural England at its best. Wild flowers grow in the fields, sparkling moorland streams cascade down the valley sides and there are old-fashioned country pubs in the villages. Enjoy the best views by walking or cycling. Every year the two-week Swaledale Festival takes place with music and guided walks.
Life in Newcastle Gateshead revolves around the River Tyne and the Gateshead Millennium Bridge is an essential part of the city's culture linking Newcastle Quayside and Gateshead Quays. As the world's first tilting bridge, the pedestrian and cyclist crossing is one of England's most stunning structures turning on pivots on both sides of the river to form a gateway arch, which resembles the opening and closing of a giant eyelid.
Poets, painters and writers have all fallen in love with this truly beautiful lake in the Lake District, Cumbria. Wastwater is the deepest of all the lakes in the national park and in England. The three-mile long waters are surrounded by mountains and some of England's highest peaks including Scafell Pike, Great Gable and Lingmell. Its remoteness adds to its appeal with the only road in the area is off the main coastal A595.