Указатель маршрута находится рядом с укрытием.

Because маршрута is in the genitive singular.

In Russian, one noun often modifies another by putting the second noun in the genitive case. So:

• указатель = sign, marker, indicator
• маршрута = of the route

So указатель маршрута literally means route sign / marker of the route.

This is very common in Russian:

• центр города = city center
• начало пути = beginning of the path
• номер дома = house number

So this is not possession in the English ’s sense only; it is a very normal way to connect nouns.

Because the expression рядом с requires the instrumental case.

The base form is:

• укрытие = shelter, cover

After рядом с it becomes:

• с укрытием = near the shelter

So the pattern is:

• рядом с домом = next to the house
• рядом с дорогой = next to the road
• рядом с укрытием = next to the shelter

Even though с often means with, here it is part of the fixed expression рядом с, meaning next to / near.

It usually means near, beside, or next to.

The exact distance depends on context. It often suggests fairly close proximity, but not necessarily touching.

So рядом с укрытием could mean:

• near the shelter
• beside the shelter
• next to the shelter

If you want to make it sound even more immediate, Russian can add words like:

• прямо рядом с = right next to
• совсем рядом с = very near

Находится means is located / is situated / is found.

Russian often omits to be in the present tense when simply saying X is Y, but with location, a verb like находится is very common, especially in neutral or slightly formal descriptions.

So:

• Указатель маршрута рядом с укрытием = possible in some contexts, but more compressed
• Указатель маршрута находится рядом с укрытием = the route marker is located near the shelter

Using находится sounds clearer and more complete, especially in:

• directions
• instructions
• official descriptions
• game/map text

It is a bit more formal or descriptive than simple everyday speech, but it is still very normal.

Compare:

• Указатель маршрута находится рядом с укрытием = neutral, descriptive, slightly formal
• Указатель маршрута рядом с укрытием = shorter, more conversational or note-like

So the original sentence sounds natural, especially if it appears in a guide, directions, a game, a map description, or an informational text.

Yes. Russian word order is flexible, though the basic meaning stays the same.

The original sentence:

• Указатель маршрута находится рядом с укрытием.

A common alternative:

• Рядом с укрытием находится указатель маршрута.

This version puts more focus on the location first: Near the shelter, there is a route marker.

In Russian, word order often affects focus or emphasis, not the core grammar.

Here is a quick breakdown:

• указатель
  dictionary form: указатель
  part of speech: noun
  gender: masculine
  number: singular
  case here: nominative
  role: subject

• маршрута
  dictionary form: маршрут
  part of speech: noun
  gender: masculine
  number: singular
  case here: genitive
  role: modifies указатель

• находится
  dictionary form: находиться
  part of speech: verb
  tense: present
  person/number: 3rd person singular
  meaning: is located

• рядом с
  fixed expression meaning near / next to

• укрытием
  dictionary form: укрытие
  part of speech: noun
  gender: neuter
  number: singular
  case here: instrumental
  role: object of рядом с

Because Russian has no articles.

So указатель маршрута can mean:

• a route marker
• the route marker

The exact meaning depends on context.

English learners often want a one-to-one match for a/the, but Russian simply does not mark that grammatically in most cases. Context tells you whether the speaker means something definite or indefinite.

By itself, с укрытием can indeed mean with a shelter in some contexts.

But in this sentence, it is part of the fixed phrase рядом с, so it clearly means near the shelter.

So:

• рядом с укрытием = near the shelter

You should learn рядом с as one unit, because the preposition с here is not being used independently.

A helpful stress pattern is:

указа́тель маршру́та нахо́дится ря́дом с укры́тием

Approximate notes:

• указа́тель — stress on а
• маршру́та — stress on у
• нахо́дится — stress on хо
• ря́дом — stress on я
• укры́тием — stress on ы

Getting the stress right matters a lot in Russian, because it is not always predictable from spelling.