If you decide to climb right to the top of the Law, you will see magnificent views of East Lothian in all directions, Edinburgh far to the west, and over the Forth of Firth to Fife. Otherwise this is still a nice walk around a hill.
For SatNav, the nearest post code is EH39 4QZ, the primary school opposite the Law entrance.
Leave the A1 at the roundabout at the east side of Haddington and head for East Linton. About 1.5 miles down the road, take the B1347 road signposted North Berwick, Flag Heritage Centre and National Museum of Flight. After about 4 miles you will come to a T junction, turn left for North Berwick. Keep following the B1347 for North Berwick and you will see the Law ahead of you. As you round the Law and reach houses you will see a road on your right signposted 'P The Law'. Take this road and the car park is about 100 yards down.
You can see a map of the route here.
From the car park go through the gap in the wall and follow the path to the right round the base of the hill. After a while the path passes a walled garden, and about half way along there is a left hand branch going up the hill. Take this path. Now there are several paths up the hill, but the easiest is to follow the wider path, which rounds to the south of the hill then forks again, with the right hand fork going round the hill and the left hand one going up. Here you have a choice, you can turn right and miss out the steep climb, but to get those views, turn left and up. So, turn left and the path doubles back and up, still not too steeply, and takes you to a bench with a grand view over North Berwick.
Now comes the real climb. You can tackle the south side, which is a steep but direct climb up a very rocky path, or go past the seat and climb the north side, which is a bit easier. Once you are at the top you will see an artificial whalebone arch, a trig point, a view indicator and some ruins. Reflect for a while on the effort involved in hauling that lot up the hill, while enjoying the stunning views. As the Law stands alone, you can see for miles in every direction.
Now you have to go down again. I'd certainly recommend the north side for the descent as the south side is too steep. Go back down the hill to the seat, and then a bit further down to the fork in the path. Now take the other path, and follow it right round the hill and back to the car park.
When you get back to your car, consider a look at North Berwick. It has a few nice shops and cafes. And, once you have had a coffee and a rest, take a look at the beach.
Over 350 million years ago the Lothain area suffered from a lot of massive volcanic eruptions, which produced cones of hard rock. These rocks were buried under ash and layers of soft sediment until the last ice age when huge glaciers moving down the Forth valley ground the softer rocks away and left the hard volcanic cones behind. One of these cones was North Berwick Law, others include the Bass Rock, Edinburgh Castle Rock, Arthur's Seat and Traprain Law.
In Roman times, the Law was a major Votadini settlement, and around 20 hut circles and dykes exist on the hill from these times.
In 1709 a whale's jawbone was erected on top of the hill, and it was replaced in 1933, but the last one rotted away. A fibreglass replica was donated to the town in 2007, however unlike the real bones, this one was airlifted into place.
There is an infamous tale about North Berwick. In the mid 16th century, King James VI was returning from Copenhagen with his new Danish bride when their ship was wracked by severe storms. The storms were blamed on witches and two women were burned in Copenhagen. When he got home, King James decided to check for a Scottish connection.
A young servant called Gilly Duncan was tortured and confessed to have participated in a coven at North Berwick Old Kirk in 1590. Between 70 and 200 witches were put on trial, tortured in the most brutal way and even executed, from the town of North Berwick and the surrounding area. This must have been a sizable proportion of the population. Apparently the witches were supporters of Francis Boswell, who was a rival to James. He was exiled, the so-called witches were tortured, burned and hanged.
On a lighter note, there has been claims of UFO sightings from the Law, so keep a good lookout when you are up there!