Krepost Sveaborg - Land Front

Land Front

To protect Krepost Sveaborg and the naval base in particular from a German attack from land the fortifications were built to protect the fortress. The first fortifications were hastily built in 1914 to block access to the Helsinki peninsula and to guard the eastern flank of Laajasalo and Santahamina by a scarce line of fortifications at Ruskeasuo-Pasila-Käpylä-Koskela-Viikki-Herttoniemi-Roihuvuori. Lauttasaari, Meilahti and Laajasalo were also fortified to some extent. It was also planned to fortify Kulosaari and Vartiosaari. These first fortifications were field fortifications located 6–7 km (3.7–4.3 mi) from the city center, with the defence concentrated at fortified hilltop redoubts.

In early 1915 it was decided to build new defenses further away from the city center. The new defenses were stronger fixed fortifications with positions quarried into rock or dug into ground. Fortifications were built from wood and stone masonry as well as concrete. New fortifications had a network of defensive structures, with trenches, rifle pits, machine gun nests, barbed wire obstacles, shelters and roads. Artillery batteries were located 0.5–1.5 km (0.31–0.93 mi) behind the front line, often located on reverse slope. Artillery batteries had 2-6, typically four, guns. Heavily fortified caponiers providing flanking fire were built on places of the front line. First a northern line was built at Leppävaara-Kaarela-Pakila-Pukinmäki-Myllypuro-Vartiokylä. Construction on a western line from Leppävaara to Westend via Tapiola began shortly afterwards. In late 1915 it was decided to build an outer line of defence on the northern and eastern sectors, extending the fortifications northward and in the east from Pukinmäki to Malmi, Mellunkylä and Vuosaari. Fortification works continued until the February revolution of 1917, and some work was done until early 1918. The land front was divided into three sectors, eastern, northern and western with 36 bases, numbered I-XXXVII. The bases were usually centered on hilltops with the strongest defences.

The basic front line fortifications were open or covered machine gun nests, rifle pits, observation posts and shelters. Most of the structures were designed to be covered with a concrete roof poured on wooden planks occasionally reinforced with railway tracks. Some of the positions were built with stone or logs. Many of the fortifications have been left uncovered however, built only to a point where adding the missing roof could be accomplished quickly. The basic fortified types are a type A square machine gun nest, type B square rifle or machine gun pit, type C rounded rifle or observation pit, type D oval rifle pit with several firing ports and types E and F large rifle positions for multiple shooters. There is considerable variation between individual structures among the basic types, with newer positions generally built larger and stronger.