# Marne et Seine bus network

Marne et Seine bus network is a public bus transport network operating in the Île-de-France region, organized by the organizing authority Île-de-France Mobilités. It has been operated by the Transdev group through the company Transdev Coteaux de la Marne since August 1, 2023. The network operator will also operates the future Câble 1.
The network consists of 26 routes, including nine school routes and one express route.
On April 8, 2024, the network will follow the new regional numbering of bus lines and will take the numbers 427 to 451.

## History
### Network development
#### Competition opening

Due to the opening up of public transport to competition in Île-de-France, the Marne et Seine bus network will be created on 1 August 2023, corresponding to public service delegation number 21 established by Île-de-France Mobilités. A call for tenders was therefore launched by the organizing authority in order to designate a company that will operate the network for a period of eight years. It was finally Transdev, via its subsidiary Transdev Coteaux de la Marne, which was designated during the board of directors of December 7, 2022.
The network consisted of SITUS ex-routes 2, 7, 8, 10, 21, 22, 41, 42, 51, 71, 81 and 82 while operated by CEA Transports, lines 1, 3, 4, 5, 6, 9 of SITUS and route 12 of Arlequin operated by Transdev SETRA, plus the routes B, J1, J2, K, O1, O2 and U of Transdev STRAV.
On January 1, 2024 and following the end of the outgoing contract, the Express 100 Torcy-Créteil route is taken over by Transdev Coteaux de la Marne.

#### Routes renaming

As of April 8, 2024, the Marne et Seine network will apply the new single regional numbering principle planned by Île-de-France Mobilités, removing duplicates and letters. The correspondence between old and new numbers is as follows: lines J1 and J2 merge into a single line 427 and lines 429 and 430 get new routes.:
Network renaming :
| Old route | New route |
| J1+J2 | 427 |
| K | 428 |
| O1 | 429 |
| O2 | 430 |
| 1 | 431 |
| 2 | 432 |
| 3 | 433 |
| 4 | 434 |
| 5 | 435 |
| 6 | 436 |
| 7 | 437 |
| 8 | 438 |
| 9 | 439 |
| 10 | 440 |
| 21 | 441 |
| 22 | 442 |
| 41 | 443 |
| 42 | 444 |
| 51 | 445 |
| 71 | 446 |
| 81 | 447 |
| 82 | 448 |
| U | 449 |
| B | 450 |
| 12 | 451 |

## Routes
### Marne et Seine

| Bus | Between | And |
| 427 | Boissy-Saint-Léger RER | Villeneuve-Saint-Georges — Les Graviers |
| 428 | Villeneuve-Saint-Georges RER | Créteil — Préfecture |
| 429 | Créteil–L'Échat | Limeil-Brévannes — Emile Combes - Descartes |
| 430 | Boissy-Saint-Léger RER | Créteil–L'Échat |
| 431 | Sucy–Bonneuil RER | École des Bruyères |
| 432 | Sucy–Bonneuil RER | Mairie de Noiseau Émerainville - Pontault-Combault RER |
| 433 | Sucy–Bonneuil RER | Noiseau – Claude Monet |
| 434 | Sucy–Bonneuil RER | Sucy-en-Brie – Les Monrois Lycée de Sucy |
| 435 | Sucy–Bonneuil RER | Boissy-Saint-Léger RER |
| 436 | Les Boullereaux-Champigny RER | Boissy-Saint-Léger RER |
| 437 | Champigny - Saint-Maur RER | Pontault-Combault – Centre Commercial Les 4 Chênes |
| 438 | La Varenne–Chennevières RER | Chennevières-sur-Marne – Centre Commercial Pince Vent |
| 439 | Sucy–Bonneuil RER (circular line) | Sucy–Bonneuil RER (circular line) |
| 440 | Sucy–Bonneuil RER | Chennevières-sur-Marne – Centre Commercial Pince Vent |
| 441 | Sucy–Bonneuil RER | Sucy-en-Brie – Collège du Fort |
| 442 | Noiseau – La Garenne | Sucy-en-Brie – Collège du Parc/Parc de Sucy |
| 443 | Sucy–Bonneuil RER | Sucy-en-Brie – Collège du Fort |
| 444 | Sucy-en-Brie – Les Berges | Sucy-en-Brie – Collège du Fort |
| 445 | Boissy-Saint-Léger RER | Groupe scolaire Amédée Dunois |
| 446 | La Queue-en-Brie — Petit Caporal | Chennevières-sur-Marne — Lycée Champlain |
| 447 | Chennevières-sur-Marne — Moulin Vert | Collège Molière |
| 448 | Chennevières-sur-Marne — Moulin Vert | Lycée Champlain |
| 449 | Villecresnes (circular route) | Villecresnes (circular route) |
| 450 | Créteil–L'Échat | Yerres — Abbaye/Cimetière Brunoy RER |
| 451 | Créteil-Préfecture Boissy-Saint-Léger RER | Servon — Centre commercial Eden |

### 100 Torcy-Créteil

| Image | Bus | Between | And |
| | 100 Torcy-Créteil | Torcy RER | Créteil–L'Échat |