Choosing the "best" hiking route in the UK really depends on your preferences, fitness level, and what kind of scenery you enjoy. Here are a few renowned options across different regions:

West Highland Way (Scotland): This long-distance trail covers 96 miles (154 km) from Milngavie, just outside Glasgow, to Fort William. It takes you through some of Scotland's most stunning scenery, including Loch Lomond and the rugged landscapes of the Scottish Highlands.

Hadrian's Wall Path (England): Following the historic Hadrian's Wall, this 84-mile (135 km) trail stretches across the north of England, from Wallsend in the east to Bowness-on-Solway in the west It offers a mix of countryside, Roman ruins, and charming villages.

The Pennine Way (England and Scotland): One of the UK's toughest long-distance trails, the Pennine Way spans 268 miles (431 km) from Edale in the Peak District to Kirk Yetholm in the Scottish Borders. It crosses some of England's most rugged and remote terrain, including the Pennines and the Cheviot Hills.

The South West Coast Path (England): This trail follows the stunning coastline of southwest England, covering a total distance of 630 miles (1,014 km). You can choose shorter sections or tackle the entire route, which takes you through quaint seaside villages, rugged cliffs, and sandy beaches.

The West Highland Way (Scotland): Stretching 96 miles (154 km) from Milngavie, near Glasgow, to Fort William, this trail offers a fantastic journey through Scotland's beautiful landscapes, including Loch Lomond and the Scottish Highlands.

The Snowdonia Way (Wales): This 97-mile (156 km) trail takes you through the heart of Snowdonia National Park, offering breathtaking views of mountains, lakes, and forests. It starts in Machynlleth and finishes in Conwy, with Snowdon itself as a highlight along the way.
 

These are just a few examples, and there are countless other trails and routes to explore throughout the UK, catering to all levels of hikers and outdoor enthusiasts.