Tallinn's main attraction is its old centre, where the main sights are. People have been living here for at least five thousand years and the first fortress was built on the hill at the end of the 10th century.
The historic centre is divided into Cathedral Hill or Toompea, where the aristocracy lived, and the Old Town below it, for tradesmen. By the 14th century there were already 8 000 people within the city walls, defended by 45 towers.
Both parts of the historic centre are beautifully preserved, not as a museum but as a place where people still live and work. The main sights are best seen simply by walking through the town. The streets are too narrow for buses anyway.
The map shows a simple route through the Old Town, from the Great Coastal Gate via Town Hall Square to Viru Gate, where the modern shopping area begins. It is about 1.2 km (¾ mile) long.
GREAT COASTAL GATE
Just outside the old town walls, by Fat Margaret Tower, is the Broken Line monument (point 1 on the map). It commemorates the 852 people who lost their lives in 1994, when the Estonia cruiseferry sank on her way to Stockholm.
Inside Fat Margaret Tower itself is the Maritime Museum 2 on four floors. You can also take the stairs to the roof for a great view of the harbour in one direction and the Old Town in the other.
ST OLAV'S CHURCH
Starting from the Great Coastal Gate is Pikk, meaning Long Street, which stretches most of the way across the Old Town. Parallel to it is Lai, meaning Wide Street, which is almost as long and of course wider. At the beginning of Lai is the tallest building in Europe.
Or at least it was in 1500, when the spire of St Olav's Church 3 was built. It was 159 meters tall, to make Tallinn's harbour easy for merchant ships to find.
The spire has been rebuilt several times after being struck by lightning and destroyed 
by fires visible as far away as Finland. It is now not quite so tall.
The church itself is impressively large but its interior is a disappointment. Most of its decorations, works of art and 25 fine altars were removed during the 16th century in the Lutheran Reformation, when religious symbols were despised.
For a small price you can ascend the 60 metres (200 feet) to the top of the tower. This is not a climb to be undertaken lightly. The passage is steep and dark. The first landing is after 160 steps and there are 96 more steps to the top.
The view of the Old Town is excellent, but the walkway is narrow. If you are afraid of heights, you will hate every moment.
TOWN HALL SQUARE
Just up the road, when Pikk meets Pühavaimu (Holy Spirit Street), is a church that survived the Reformation rather better. The Church of the Holy Spirit 4 still looks much as it did when it was built in the 14th century.
Its altar is one of the most precious medieval works of art in Estonia. Outside is a magnificent painted clock, from the 17th century.
A short alley crowded with craft boutiques leads from here to Town Hall Square 5 or Raekoja plats. This is the crowning glory of Old Tallinn, a magnificent medieval square around the only surviving Gothic town hall in the North of Europe. The surrounding buildings are brightly coloured, the limestone Town Hall is gleaming white.
From the square's south-east corner, a passage leads to Viru Street, the main shopping street of the Old Town. Just before Viru Gate, there is a well preserved section of wall 6. The new central shopping area, and a tram stop for the return trip to the harbour, lie just beyond.
