The Big Half: Complete Training and Race Guide

The Big Half has quickly become a favourite on the UK running calendar. It offers a proper big-city half marathon experience, with iconic London landmarks and huge crowd support, while keeping a friendly, community spirit that welcomes first-timers and seasoned club runners alike. This guide covers what the race is, what the route feels like underfoot, how to secure a place, and a simple 12-week plan to get you to the start line ready to enjoy it. All race facts here were checked against London Marathon Events, the organiser, as of July 2026, and details can change from year to year, so always confirm the specifics on the official site before you enter.

What is The Big Half?

The Big Half is a 13.1-mile half marathon in London, organised by London Marathon Events, the same team behind the London Marathon. It starts next to Tower Bridge and finishes beside the Cutty Sark in Greenwich, passing through the boroughs of Tower Hamlets, Southwark, Lewisham and Greenwich. London Marathon Events describes it as a vibrant, inclusive half marathon that celebrates the diversity of London, and that spirit shows up in the atmosphere on the day.

First held in 2018, the event pairs the buzz of a major city race with a genuinely community-minded feel. There is a festival area near the finish, and the organiser provides facilities such as a sensory calm space, a multi-faith prayer space and accessible toilets, along with support for participants with disabilities. That mix of big-event energy and inclusive touches is a big part of why so many people choose it for a first half marathon or a memorable return to racing. It is a separate event from the Hackney Half and the London 10K, with its own route and its own character.

What is the route like?

The course is best described as fast and mostly flat, with a few points that ask for a little patience. From the start next to Tower Bridge, the route heads out towards Limehouse and the towers of Canary Wharf, then works its way back through Wapping, Bermondsey, Rotherhithe and Deptford before the finish by the Cutty Sark in Greenwich. Crossing Tower Bridge is a highlight that many runners rate as one of the best moments of the day.

It is not entirely pancake-flat. There are gentle climbs around miles two and three as you come out of the tunnel section and head into the Canary Wharf area, a short incline near Tower Bridge, and a brief rise over a bridge in the closing stretch. There are also some narrower and cobbled sections, so it pays to run tangents sensibly and stay aware of runners around you. None of this is severe, and with steady pacing the course rewards you with a strong, celebratory finish.

How do you get a place?

There are three main ways in: general entry, a charity place, or a community place. General entry usually opens well ahead of the event and can sell out, so it is worth registering your interest early on the official site to hear when places go live. As of July 2026, general entry for the 2026 race has sold out, but charity places are still available.

A charity place is a great option if the standard entry has gone. You run on behalf of a chosen charity, and this typically involves a registration fee plus a fundraising pledge, both of which vary by charity, so check the details with the charity directly. Community places are aimed at residents of the boroughs the route passes through. There is also a minimum age to take part, so confirm the current requirement before you commit. Because entry windows, fees and field sizes are set fresh each year, the most reliable place to check everything is the official Big Half website, which is the authoritative source for entry.

How should you train for a half marathon?

Assuming you already have a basic running base and can comfortably run for around half an hour, roughly 12 weeks is a sensible runway to prepare for The Big Half. The core idea is simple: most of your running should be easy and conversational, one session each week adds a little quality, and a weekly long run gradually builds the endurance you need for 13.1 miles. Progress the long run steadily, then ease back before race day so you arrive fresh.

Strength and mobility work is widely recommended to support your running, help you feel robust and keep training consistent. Two short sessions a week covering the legs, hips and core is plenty alongside your runs. If you have any pain, an injury or a health condition, see a physio or GP before pushing on. The outline below is a starting framework you can adapt to your own schedule and how you feel, with an easier week to absorb the work and a taper at the end.

Distances are a guide. Keep easy runs genuinely easy, and move sessions around to fit your week rather than forcing a hard day when you feel run down.

How should you pace it?

The most common mistake at a big, exciting race is going out too fast. The crowds and the energy over Tower Bridge make quick early miles feel effortless, right up until they are not. Aim to start a touch slower than your target pace, settle into a rhythm you could hold in conversation for the first few miles, and let the effort build gradually. A small negative split, running the second half a little quicker than the first, is a reliable way to finish strong.

Plan for the terrain. Ease off slightly on the short climbs around miles two and three rather than fighting them, and let the flatter, faster sections do the work. Take on fluids regularly and use any planned fuel on schedule instead of waiting until you feel low. When you make the final turn and the Cutty Sark comes into view, that is the time to spend whatever you have left.

What should you know on race day?

Arrive in good time at the start next to Tower Bridge, allowing for busy public transport and the walk to your assembly area. Lay out your kit the night before, pin your number, and nothing new on race day applies to shoes, socks, kit and fuel, all of which should be tried in training first. Check the baggage and start arrangements in your final event information so you know where to be and when.

Dress for early-autumn London weather, which can be mild or cool, and consider an old top you can discard once warmed up. There is a generous course cut-off of around four hours with walkers supported to finish, so there is room to take it at your own pace. Soak up the community atmosphere through the four boroughs, thank the volunteers, and enjoy the festival finish by the Cutty Sark. It is a race designed to be experienced, not just completed.

Frequently asked questions

What is The Big Half and how do you enter?

The Big Half is a 13.1-mile half marathon in London, run by London Marathon Events. It starts next to Tower Bridge and finishes by the Cutty Sark in Greenwich, and it is known for a friendly, inclusive, community feel. You enter through general entry, a charity place or a community place via the official site. As of July 2026, general entry for the 2026 race has sold out, while charity places remain available.

When is The Big Half 2026?

The next event is Sunday 6 September 2026. Dates are set fresh each year, so confirm the current date on the official site.

How long is The Big Half?

It is a half marathon, 13.1 miles or about 21.1 km, on a route that is mostly flat and fast with a few short climbs.

Is The Big Half good for beginners?

Yes. With its inclusive atmosphere, generous cut-off of around four hours and strong crowd support, it is a popular choice for a first half marathon, provided you follow a sensible training build like the 12-week outline above.

How long does it take to train for it?

If you already run a little, around 12 weeks is a reasonable window to build safely to the distance, with most running kept easy, one weekly session and a long run that grows steadily before a taper.

Race facts in this guide were checked against London Marathon Events, the organiser of The Big Half, as of July 2026. Entry routes, fees, dates and field sizes change from year to year, so always confirm current details at thebighalf.co.uk before entering. This article is general information and not medical advice.